Austin does his Power lifting every morning to stay in shape. He lifts a 90 kg barbell, 2.3 m above the ground.a) How much energy does it have when it was on the ground? Jb)How much energy does it have after being lifted 2.3 m? Jc) What kind of energy does it have after being lifted? d) How much work did Austin do to lift the barbell? Je) If he lifted it in 1.9s, what was his power? W

Answers

Answer 1

ANSWER

[tex]\begin{gathered} (a)0J \\ (b)2030J \\ (c)\text{ Potential energy} \\ (d)2030J \\ (e)1070W \end{gathered}[/tex]

EXPLANATION

Parameters given:

Mass of barbell, m = 90 kg

Height above ground, h = 2.3 m

(a) We want to find the energy the barbell has on the ground. #

When it is on the ground, the barbell is stationary, which means its velocity is 0 m/s, hence, its kinetic energy is also 0 J, since kinetic energy is given as:

[tex]\begin{gathered} KE=\frac{1}{2}mv^2 \\ KE=\frac{1}{2}\cdot m\cdot0=0J \end{gathered}[/tex]

Also, on the ground, it is at a height of 0 m, hence, its potential energy is 0 J:

[tex]\begin{gathered} PE=mgh \\ PE=m\cdot g\cdot0=0J \end{gathered}[/tex]

where g = acceleration due to gravity

Therefore, on the ground, the energy the barbell had was 0 J.

(b) After it had been lifted 2.3 m, its height above the ground became 2.3 m.

Now, we can find the potential energy possessed by the barbell:

[tex]\begin{gathered} PE=90\cdot9.8\cdot2.3 \\ PE=2028.6J\approx2030J \end{gathered}[/tex]

After it is lifted, it is once again stationary, hence, it has no kinetic energy.

Therefore, the energy the barbell has after it has been lifted 2.3 m is 2070J.

(c) As stated in (b) above, after being lifted, the barbell only possesses potential energy since it is at a height above the ground and it is not moving.

(d) The work done in lifting the barbell is equal to the force applied multiplied by the height moved by the barbell.

That is:

[tex]W=F\cdot d[/tex]

The force applied is equal to the weight of the barbell:

[tex]\begin{gathered} F=W=mg \\ F=90\cdot9.8 \\ F=882N \end{gathered}[/tex]

Therefore, the work done is:

[tex]\begin{gathered} W=882\cdot2.3 \\ W=2028.6J\approx2030J \end{gathered}[/tex]

(e) He lifted the barbell in 1.9 seconds. To find his power, we have to divide the work done by the time taken to do the work.

That is:

[tex]\begin{gathered} P=\frac{W}{t} \\ P=\frac{2030}{1.9} \\ P=1068.4W\approx1070W \end{gathered}[/tex]

That was his power.


Related Questions

A.Calculate the combined force of vector F ?B.Calculate the direction of the combined force vector F ?

Answers

Answer:

A. 282.93 N

B. 1.94 degrees

Explanation:

The combined force is found by first adding the three forces given.

We add the three forces by adding their x and y components separately and then combining the results to produce the total force,

The x component of a force is

[tex]\begin{gathered} \cos \theta=\frac{f_x}{F} \\ \Rightarrow f_x=F\cos \theta \end{gathered}[/tex]

Therefore, x components of the forces is

[tex]F_x=120\cos 65+100\cos 25+200\cos (-45)[/tex]

The y-component of the forces is

[tex]F_y=120\sin 120+100\sin 25+200\sin (-45)[/tex]

Now evaluating the above two components gives

[tex]F_x=282.77N[/tex][tex]F_y=9.597N[/tex]

Let us draw on big vector whose components are the above vectors.

The angle of the combined vector with respect to the x-axis is

[tex]\tan \theta=\frac{9.59}{282.77}[/tex][tex]\theta=\tan ^{-1}(\frac{9.59}{282.77})[/tex][tex]\boxed{\theta=1.94^o}[/tex]

which is our answer!

The magnitude of the combined vector is

[tex]F=\sqrt[]{F^2_x+F^2_y_{}}[/tex][tex]F=\sqrt[]{(9.59)^2_{}+(282.77)^2_{}}[/tex][tex]\boxed{F=282.93N}[/tex]

which is our answer!

Hence, to summerise:

A. 282.93 N

B. 1.94 degrees

Can all rocks be dated with radiometer methods? Explain

Answers

Answer: No.

Explanation:

Radiometer dating is used on igneous rocks.

Unlike the other two rock types, sedimentary annd metamorphisis, all igneous rocks possess one specific age/ time of origin.

A roller coaster car begins its roll from the top of the tracks at a speed of2 meters per second. When it reaches the bottom of the 200-meter drop four seconds later, its speed is 22 meters per second. What was the averagespeed of the roller coaster ride in meters per second over the 200-meter drop

Answers

The speed of the car from the top of the track is,

[tex]u=2ms^{-1}[/tex]

The distance traveled by the car is,

[tex]d=200\text{ m}[/tex]

The speed of the car after 4 seconds is,

[tex]v=22ms^{-1}[/tex]

Thus, the average speed of the car is,

[tex]v_{av}=\frac{u+v}{2}[/tex][tex]\begin{gathered} v_{av}=\frac{2+22}{2} \\ v_{av}=12ms^{-1} \end{gathered}[/tex]

Thus, the average speed of the roller coaster car is 12 meter per second.

Describe the mathematical relationship between the distance (d) and the attractive force (F) between protons and electrons.

Answers

The attractive force and the distance are inversely proportional.

[tex]F\propto\frac{1}{r}[/tex]

This relation means that the attractive force decreases as the distance increases, and the attractive force increases as the distance decrease.

7. What is the velocity of a 850kg car after starting at rest when 13,000J of work is done to it.

Answers

Answer:

5.53 m/s

Explanation:

The work is equal to the change in the kinetic energy, so

[tex]\begin{gathered} W=\Delta KE \\ W=\frac{1}{2}m(v^2_f-v^2_i)^{}^{} \end{gathered}[/tex]

Since the car starts at rest, the initial velocity vi = 0 m/s, so we can solve for the final velocity vf as follows

[tex]\begin{gathered} W=\frac{1}{2}mv^2_f \\ 2W=mv^2_f \\ \frac{2W}{m}=v^2_f \\ v_f=\sqrt[]{\frac{2W}{m}} \end{gathered}[/tex]

So, replacing the work W = 13,000J and the mass m = 850kg, we get:

[tex]\begin{gathered} v_f=\sqrt[]{\frac{2(13,000J)}{850\operatorname{kg}}} \\ v_f=5.53\text{ m/s} \end{gathered}[/tex]

Therefore, the velocity is 5.53 m/s

What word am I looking for I have already tried losing

Answers

We will have the following:

neutral object becomes charged by losing electrons.

A penny is dropped from a building and it takes 7.00 seconds to hit the ground.

Answers

Based on the given question, the final velocity of the penny is 68.6m/s

Calculations and Parameters

Based on the definition of velocity, we can see that it has to do with the speed at which an object moves with at a particular direction.

If we observe the 1st law of motion:

v = u + gt

Where:

v = final velocity

u = initial velocity

g = acceleration due to gravity

t = time taken

We need to find the velocity as it was not given.

We already know that

u = 0 (it was at rest),

t = 7s

v = unknown

Let us put in the given values based on the equation and solve for the answer.

v = u + gt

v = 0 + ( 9.8m / s ² × 7.00s )

v = 9.8m / s ² × 7.00s

v = 68.6m/s

Therefore, the final velocity of the penny is 68.6m/s

Read more about velocity here:

https://brainly.com/question/25749514

#SPJ1

A penny is dropped from a building, and it takes 7 seconds to hit the ground, so the final velocity will be 68.6 m/s.

What is Velocity?

The ratio of displacement to time is referred to as velocity of the object. It has SI unit meter per second or m/s and has a dimension formula LT⁻¹.

We already know that

Initial speed, u = 0

Time, t = 7 seconds

Use the equation of motion to find the final velocity,

v = u + gt

v = 0 + ( 9.8 m / s ² × 7.00s )

v = 9.8 m / s ² × 7.00s

v = 68.6 m/s

Hence, the penny hit the ground with a final velocity of  68.6 m/s.

To get more information about Velocity :

https://brainly.com/question/18084516

#SPJ1

A runner runs around a circular track. He completes one lap at a time of t = 314 s at a constant speed of v = 3.1 m/s. t = 314 sv = 3.1 m/sWhat is the radius, r in meters, of the track? What was the runners centripetal acceleration, ac in m/s2, during the run?

Answers

Since the runner completes 1 lap in 314 seconds, and its velocity is 3.1m/s, then the total distance covered in 1 lap is:

[tex]\begin{gathered} d=vt \\ =(3.1\frac{m}{s})(314s) \\ =973.4m \end{gathered}[/tex]

That distance corresponds to the perimeter of the circumference. The perimeter of a circumference with radius r is 2πr. Then:

[tex]\begin{gathered} 2\pi r=d \\ \\ \Rightarrow r=\frac{d}{2\pi} \\ =\frac{973.4m}{2(3.14...)} \\ =154.9...m \end{gathered}[/tex]

The centripetal acceleration of an object in a circular trajectory with radius r and speed v is:

[tex]a_c=\frac{v^2}{r}[/tex]

Replace v=3.1m/s and r=154.9m to find the centripetal acceleration:

[tex]a_c=\frac{(3.1\frac{m}{s})^2}{(154.9m)}=0.062\frac{m}{s^2}[/tex]

Therefore, the radius of the track is approximately 155m and the centripetal acceleration of the runner is approximately 0.062 m/s^2.

what is the velocity of the boat from point x to point y

Answers

The distance between the points X and Y is,

[tex]\begin{gathered} d=9\text{ km} \\ =9000\text{ m} \end{gathered}[/tex]

The time taken to move the distance is,

[tex]\begin{gathered} t=12\text{ min} \\ =12\times60\text{ s} \end{gathered}[/tex]

The velocity is given by,

[tex]\begin{gathered} v=\frac{d}{t} \\ =\frac{9000\text{ m}}{12\times60\text{ s}} \\ =12.5\text{ m/s} \end{gathered}[/tex]

Hence the velocity is 12.5 m/s.

Suppose a 345-g kookaburra (a large kingfisher bird) picks up a 75-g snake and raises it 2.1 m from the ground to a branch.How much work, in joules, did the bird do on the snake? How much work, in joules, did it do to raise its own center of mass to the branch?

Answers

The work done in each case can be calculated with the change in potential energy of the body:

[tex]Work=m\cdot g\cdot h[/tex]

The work done by the bird on the snake will use only the mass of the snake (in kg):

[tex]\begin{gathered} Work=0.075\cdot9.8\cdot2.1\\ \\ Work=1.5435\text{ J} \end{gathered}[/tex]

The work done by the bird to raise its own center of mass will use only the bird mass (in kg):

[tex]\begin{gathered} Work=0.345\cdot9.8\cdot2.1\\ \\ Work=7.1\text{ J} \end{gathered}[/tex]

How does the work needed to stretch a spring 2 cm compare to the work needed to stretch it 1 cm.A.Same amount of workB.twice the workC.4 times the work D.8 times the work

Answers

The work required to stretch a string is given by the following equation:

[tex]W=\frac{1}{2}kx^2[/tex]

Where:

[tex]\begin{gathered} k=\text{ string constant} \\ x=\text{ distance the string is stretched} \end{gathered}[/tex]

If the string is stretched 2 cm then we substitute the value of "x = 2" in the formula, we get:

[tex]W_2=\frac{1}{2}k(2)^2[/tex]

Solving the square and simplifying:

[tex]W_2=2k[/tex]

Now, if the string is stretched 1 cm we get:

[tex]W_1=\frac{1}{2}k(1)^2[/tex]

Solving the operations:

[tex]W_1=\frac{1}{2}k[/tex]

Now, we determine the quotient between W2 and W1:

[tex]\frac{W_2}{W_1}=\frac{2k}{\frac{1}{2}k}[/tex]

Simplifying we get:

[tex]\frac{W_2}{W_1}=4[/tex]

Now, we multiply both sides by W2:

[tex]W_2=4W_1[/tex]

Therefore, the work required to stretch the string 2 cm is 4 times the work to stretch it 1 cm.

A 20.0 kg penguin slides at a constant velocity of 3.3 m/s down an icy incline. The incline slopes above the horizontal at an angle of 6.0°. Determine the coefficient of kinetic friction.

Answers

The coefficient of kinetic friction down the slope is 0.105.

What is kinetic friction?

Kinetic friction is the friction that exists or acts between the surfaces of one object moving over another.

The kinetic frictional force of an object moving on an inclined plane is give by the formula below:

Kf = μk * mg *cosθ

where;

μk = coefficient of kinetic friction.

mg cosθ = component of the weight perpendicular to the inclined plane

θ = angle of inclination

For an object moving at a constant velocity, the component of the weight down the slope (mg sinθ) is equal to the kinetic frictional force.

Hence, μk * mg *cosθ = mg sinθ

μk =  mg sinθ / mg *cosθ

μk = tan θ

μk = tan 6.0

μk = 0.105

Learn more about kinetic friction at: https://brainly.com/question/20241845

#SPJ1

If the planet Mercury has a mass of planet 3.3×10²³ kg and a radius of 2400 km - calculate the magnitude of the gravitational field on its surface?

Answers

Answer:

The magnitude of the gravitational field on the surface of the planet mercury is 3.82 m/s²

Explanation:

The mass of mercury, m = 3.3×10²³ kg

The radius, r = 2400 km

r = 2400 x 1000m

r = 2.4 x 10⁶m

Note that the magnitude of the gravitational field on the surface of the planet is the acceleration due to gravity on that planet

It is given by the formula:

[tex]g=\frac{Gm}{r^2}[/tex]

Substitute the values of G, m, and r into the formula above

[tex]\begin{gathered} g=\frac{6.67\times10^{-11}\times3.3\times10^{23}}{(2.4\times10^6)^2} \\ g=\frac{6.67\times10^{-11}\times3.3\times10^{23}}{(2.4\times10^6)^2} \\ g=\frac{2.2\times10^{13}}{5.76\times10^{12}} \\ g=3.82m/s^2 \end{gathered}[/tex]

The magnitude of the gravitational field on the surface of the planet mercury is 3.82 m/s²

nd in Atlanta you decide to drive around the city. You turn a corner and are driving up a steep hill. Suddenly, a small boy runs out on the street chasing a ball. You slam on the brakes and skid to a stop leaving a 50-foot-long skid mark on the street. The boy calmly walks away but a policemen watching from the sidewalk walks over and gives you a speeding ticket. He points out that the speed limit on this street is 25mph. After you recover your wits, you begin to examine the situation. You determine that the street makes an angle of 25◦with the horizontal and that the coefficient of static friction between your tires and the street is0.80. You also find that the coefficient of kinetic friction between your tires and the street is 0.60. Your car’s information book tells you that the mass of your car is 1600 kg. You weigh 140 lbs. Will you fight the ticket

Answers

skid = 50 ft

Speed limit = 25 mph

angle = 25°

friction coefficient = 0.80

mass = 1600 kg

weight = 140 lbs

Need help 82x2682 please

Answers

ANSWER:

STEP-BY-STEP EXPLANATION:

We have the following multiplication:

[tex]undefined[/tex]

Write a 5 page research on the topic 'How do migrating birds / animals find their direction? (Two birds / animals)'. Need this ASAP.​

Answers

Answer: Birds migrate to move from areas of low or decreasing resources to areas of high or increasing resources. The two primary resources being sought are food and nesting locations. Here’s more about how migration evolved.

Birds that nest in the Northern Hemisphere tend to migrate northward in the spring to take advantage of burgeoning insect populations, budding plants and an abundance of nesting locations. As winter approaches and the availability of insects and other food drops, the birds move south again. Escaping the cold is a motivating factor but many species, including hummingbirds, can withstand freezing temperatures as long as an adequate supply of food is available.

Explanation: sorry about the anther

A car going at 80 mph comes to a complete stop in 6 seconds. Calculate the acceleration

Answers

The acceleration is defined as:

[tex]a=\frac{v_f-v_0}{t}[/tex]

where vf is the final velocity, v0 is the initial velocity and t is the time. In this case we have:

The initial velocity is 80 mph

The final velocity is 0 mph (since the car stops)

The time it takes to slow down is 6 seconds.

Before we can do the calculation, we need to convert the velocity to appropriate units; let's write the initial velocity in ft/s units. To do this we need to remember that 1 mile is equal to 5280 ft and one hour is equal to 3600 s, then we have:

[tex]80\frac{mi}{h}\cdot\frac{5280\text{ ft}}{1\text{ mi}}\cdot\frac{1\text{ h}}{3600\text{ s}}=117.33\frac{ft}{s}[/tex]

Hence the initial velocity is 177.33 ft/s.

Now that we have all the values we need, we plug them in the equation for the acceleration:

[tex]\begin{gathered} a=\frac{0-117.33}{6} \\ a=-19.56 \end{gathered}[/tex]

Therefore, the acceleration is -19.56 feet per second per second. Note: The minus sign indicates that the car is slowing down.

A ski jumper competing for an Olympic gold metal wants to jump
a horizontal distance of 149 meters. The takeoff point of the ski
jump is at a height of 38.0 meters. With what horizontal velocity
must he leave the jump in order to travel 149 meters?

Answers

19.25 m/s is horizontal velocity must he leave the jump in order to travel 149 meters .

How fast is horizontal moving?

Standard definitions of horizontal velocity include miles per hour and meters per second, which are horizontal displacement times time. The distance an object has traveled since its origin is simply referred to as displacement.

How can one calculate vertical velocity using horizontal velocity?

V * cos() equals the horizontal velocity component Vx. V * sin() is equal to the vertical component of velocity, Vy.

Time before landing = sqrt ( 2 x height / gravity ), sqrt ( 2 x 38/ 9.81) = 7.75

distance / time = avg speed

149/ 7.75 ≅ 19.25 m/s

To know more about horizontal velocity visit:-

https://brainly.com/question/14059839

#SPJ13

Full working out…….2.A vibrating mass-spring system has a frequency of 0.56 Hz. How much energy ofthis vibration is carried away in a one-quantum change?

Answers

ANSWER

3.7128 x 10⁻³⁴ J

EXPLANATION

The energy carried in a one-quantum change is the product of Planck's constant, h, and the frequency of vibration, f,

[tex]E=hf[/tex]

Planck's constant is 6.63 x 10⁻³⁴ J*s and, in this case, the frequency of vibration is 0.56 Hz. So, the energy carried away is,

[tex]E=0.56Hz\cdot6.63\cdot10^{-34}J\cdot s=3.7128\cdot10^{-34}J[/tex]

Hence, the energy carried away in a one-quantum change is 3.7128 x 10⁻³⁴ J.

Ultraviolet light has shorter wavelengths and higherfrequencies than visible light.TRUEFALSE

Answers

Ultraviolet light has shorter wavelengths and higher frequencies than visible light.

The answer is TRUE

Two drops of mercury each has a charge on 2.42 nC and a voltage of 293.97 V. If the two drops are merged into one drop, what is the voltage on this drop?

Answers

The electric potential is given by:

[tex]\begin{gathered} V=\frac{Kq}{r} \\ \end{gathered}[/tex]

Let's find r first:

[tex]\begin{gathered} r=\frac{Kq}{V}=\frac{8.988\times10^9\cdot2.42\times10^{-9}}{293.97} \\ r\approx0.074m \end{gathered}[/tex]

Now we can find the radius of the new drop:

[tex]r_t=2(r)=2(0.074)=0.148[/tex]

So:

[tex]\begin{gathered} V=\frac{K(2q)}{r_t}=\frac{8.988\times10^9\cdot2(2.42\times10^{-9})}{(0.148)} \\ V=293.93V \end{gathered}[/tex]

When you step off a bus moving at 2 m/s, your horizontal speed when you meet the ground isA) zero.B) less than 2 m/s but greater than zero.C) about 2 m/s.D) greater than 2 m/s.

Answers

ANSWER:

C) about 2 m/s.

STEP-BY-STEP EXPLANATION:

While step off the bus, it acquires a vertical component of velocity, but it still has the initial horizontal component of velocity due to the movement of the bus.

Which means that the velocity is either 2 m/s or about 2 m/s

The pressure is greater at the bottom of the bucket filled with water ,why?​

Answers

The further down you measure water, the depth increases. With more depth, there’s more water on top of that water. That water on top pushes against the water below, causing more pressure.

How long would it take to pass 700 C of charge through a toaster drawing 10 A of current? How many electrons would pass through the toaster in this time?

Answers

Given that the charge of the toaster is q =700 C

The current of the toaster is I = 10 A

We have to find the time and number of electrons.

Time can be calculated by the formula,

[tex]t=\frac{q}{I}[/tex]

Substituting the values, the time will be

[tex]\begin{gathered} t=\frac{700}{10} \\ =70\text{ s} \end{gathered}[/tex]

The number of electrons can be calculated by the formula,

[tex]n=\frac{q}{e}[/tex]

Here, n is the number of electrons

and e is the charge of the electron whose value is

[tex]1.6\text{ }\times10^{-19}\text{ C}[/tex]

Substituting the values, the number of electrons will be

[tex]\begin{gathered} n\text{ = }\frac{700}{1.6\times10^{-19}} \\ =4.375\text{ }\times10^{-17} \end{gathered}[/tex]

A) the frictional force F newtonsB)The resultant normal reaction of the surface on the metal block

Answers

Given:

The mass of the block is.

[tex]m=10\text{ kg}[/tex]

The tension on the rope is,

[tex]T=100\text{ N}[/tex]

The angle with the horizontal is,

[tex]\theta=60^{\circ}[/tex]

The block is moving with constant speed.

as the block is moving with constant speed, the net force on the block will be zero.

Part (A)

we can write in the horizontal direction the component of the tension will be equal to the frictional force and we write,

[tex]\begin{gathered} T\cos 60^{\circ}=F \\ F=100\cos 60^{\circ} \\ F=50\text{ N} \end{gathered}[/tex]

Hence the frictional force is 50 N.

\\

Part(B)

The resultant normal reaction will be,

[tex]\begin{gathered} N=T\sin 60^{\circ}-mg \\ =100sin60^{\circ}-10\times9.8 \\ =-11.4\text{ N} \end{gathered}[/tex]

hence the resultant normal reaction is -11.4 N.

Toaster uses a nichrome heating coil and operates at 120 V. When the toaster is turned on at 20°C, the current in the cold coil is 1.5 A. When the coil warms up, the current has a value of 1.3 A. If the thermal coefficient of resistivity for nichrome is 4.5x10-4 1/Co, what is the temperature of the coil?Group of answer choices68oC490oC160oC360oC260oC

Answers

Given that the operating voltage is V = 120 V.

The initial temperature of the toaster is T1 = 20 degrees Celsius

The initial current in the coil is I1 = 1.5 A

The final current in the coil is I2 = 1.3 A

The thermal coefficient of resistivity for nichrome is

[tex]\alpha=4.5\times10^{-4}^{}\text{ }^{\circ}C^{-1}[/tex]

We have to find the final temperature of the coil, T2.

The initial resistance of the coil is

[tex]\begin{gathered} R1=\frac{V}{I1} \\ =\frac{120}{1.5} \\ =80\Omega \end{gathered}[/tex]

The final resistance of the coil is

[tex]\begin{gathered} R2\text{ =}\frac{V}{I2} \\ =\frac{120}{1.3} \\ =92.307\Omega \end{gathered}[/tex]

The formula to calculate the final temperature of the coil is

[tex]\begin{gathered} \alpha=\frac{(R2-R1)}{R1(T2-T1)} \\ T2-T1=\frac{(R2-R1)}{\alpha\times R1} \\ T2=\frac{(R2-R1)}{\alpha\times R1}+T1 \end{gathered}[/tex]

Substituting the values, the final temperature will be

[tex]\begin{gathered} T2=\text{ }\frac{92.307-80}{4.5\times10^{-4}\times80}+20 \\ \approx360^{\circ}\text{ C} \end{gathered}[/tex]

Thus, the final temperature is 360 degrees Celsius.

An object is dropped from rest out of the window of a building, and the time to hit the ground is found to be 5 seconds. The same object is then dropped from rest out of a window twice as high above the ground as the original window. The time it takes the object to hit the ground is closest to:

Answers

ANSWER:

7 s

STEP-BY-STEP EXPLANATION:

Given:

u = 0m/s

t = 5 sec

g = 9.8 m/s^2

The first thing is to calculate the height of the building, using the following formula:

[tex]\begin{gathered} s=ut+\frac{1}{2}gt^2 \\ \text{ Replacing} \\ s=0\cdot5+\frac{1}{2}\cdot9.8\cdot5^2 \\ s=122.5\text{ m} \end{gathered}[/tex]

Now, we apply the same formula, but we substitute the double value of the distance and solve for t, just like this:

[tex]\begin{gathered} 2\cdot122.5=\frac{1}{2}\cdot9.8\cdot\: t^2 \\ 9.8\cdot t^2=245\cdot2 \\ t^2=\frac{490}{9.8} \\ t=\sqrt[]{50} \\ t=7.07\text{ sec} \\ t\approx7\text{ sec} \end{gathered}[/tex]

The time it takes for the object to fall is 7 seconds.

If the mass m of the wrecking ball is 3920 kg , what is the tension TB in the cable that makes an angle of 40 ∘ with the vertical? What is the tension TA in the horizontal cable?

Answers

The tension TB in the cable makes an angle of 40 ∘ and  the tension TA in the horizontal cable

TB=49380.9NTA=31741.4N

This is further explained below.

What is tension?

Generally, To represent tension in a vertical direction, the term is:

[tex]T_B=\frac{m g}{\cos \theta}[/tex]

Substitute $3860kg for m, 9.8m/s^2 for g, and 40^0 for [tex]\theta[/tex].

[tex]T_B &=\frac{(3860 \mathrm{~kg})\left(9.8 \mathrm{~m} / \mathrm{s}^2\right)}{\cos 40^{\circ}} \\[/tex]

=49380.9N

Because the cosine of the tension in the cable, which is pushing up on the item, is equal to the weight force, which is pressing down on the ground, the ball is not moving and is thus in equilibrium.

The expression for the horizontal cable tension is,

[tex]T_A=T_B \sin \theta[/tex]

Substitute $49380.9N for T_B and $40^o for [tex]\theta[/tex]

[tex]T_A &=(49380.9 \mathrm{~N}) \sin 40^{\circ}[/tex]

=31741.4N

Read more about tension

https://brainly.com/question/15880959

#SPJ1

A person pushes a 500 kg crate with a force of 1200 N and the crate accelerates at .5 m/s^2. What is the force of friction acting on the crate?

Answers

The force of friction acting on the crate is 950 N.

What is force of friction?

Force of friction is defined as the force that opposes the motion of an object when two surfaces are in contact.

The frictional force on the object is determined by applying Newton's second law of motion as shown below.

F - Ff = ma

where;

F is the applied force = 1200 NFf is the frictional forcem is the mass of the crate = 500 kga is the acceleration of the crate = 0.5 m/s²

1200   -  Ff = 500(0.5)

1200 - Ff = 250

Ff = 1200 - 250

Ff = 950 N

Thus, the force of friction acting on the crate preventing the motion of the crate is determined by applying Newton's second law of motion.

Learn more about force of friction here: https://brainly.com/question/4618599
#SPJ1

a 298 kg boat is being propelled forward with a force of 2,365 N. What is the acceleration of the boat if it has a resistance force (rewarded) due to wind and water of 878 N? (Write answer as a 2 digit number)​

Answers

The acceleration of the boat is 4.9m/s²

Mass of boat= 298 kg

Forward force= 2365 N

Resistance force= 878N

We need to apply the concept of laws of motion

Net force= Forward force- Resistance force

Net force= 2365-878 N

= 1487 N

Net force= mass x acceleration

2365= acceleration x 298

acceleration = 4.9 m/s²

Therefore, the acceleration of the boat is 4.9 m/s²

To know more about acceleration, click on https://brainly.com/question/14344386

Other Questions
which statement best characterizes product strategy for industrial products? multiple choice question. cultural differences between markets force manufacturers to substantially adapt industrial products to local markets. most companies will not sell industrial products internationally because they do not want to adapt those products to foreign markets. most industrial products require substantial changes in order to be successful in foreign markets. companies can avoid adapting products by developing products to meet the most stringent regulations. if you had only one telescope and wanted to take both visible-light and ultraviolet pictures of stars, where should you locate your telescope? DISREGARD THE LAST ONEDrag the tiles to the correct boxes to complete the pairs. Not all tiles will be used.A company manufactures computer memory chips as circular silicon wafers with a diameter of 10 Inches. The wafers are cut intodifferent sized sectors. Match each wafer's central angle to the area of that sector.4820624555 part b: which of the following quotes best supports the answer to part a Tristan and isolade python by searching the country only, answer the following questions: 1. how many movie titles mention the united states? 2. how many movie descriptions mention the united states? 3. how many movies are from the united states? Part B Which quotation from Shakespeares Sister best supportsthe answer to Part A? A one-day admission ticket to a park costs $43.85 for adults and $15.95 for children. Two families purchased nine tickets and spent $338.85 for the tickets. Fill in a chart thatsummarizes the information in the problem. Do not solve the problem. What were the three broad points of the Triangular Trade in the early Atlantic world? Forced labor from Africa, raw materials from the Americas, manufactured goods from Europe Guns from the Americas, ammunition from Europe, soldiers from Africa Capitalism from the Americas, mercantilism from Europe, animism from Africa Raw goods from Africa, industrial output from the Americas, financing from Europe What is the equation of the line that passes through the point (7,6) and has a slope of 0 Diane is on her way home in her car. Her drive is 18 miles long. She has finished two-thirds of the drive so far. How far has she driven? magine that instead of hiring each assistant right away in the hiring assistant problem, we wait until the end to hire the best one. what are the best- , worst-, and average-case costs in this case? explain The tire tread wears out in at least 60,000 miles. the tire company bought 48 tires and found out the average mile usage for 48 tires is 59,500. what hypothesis do we test to find out if the manufacturer claim is too optimistic and tires wear out before 60,000 miles? A coffee shop is having a sale on prepackaged coffee and tea. Yesterday they sold 11packages of coffee and 50 packages of tea, for which customers paid a total of $288. The daybefore, 12 packages of coffee and 38 packages of tea was sold, which brought in a total of$248. How much does each package cost? Is the exoplanet like earth in terms of its distance from its star? Explain your answer Cuanto es 25 dividido en 386,4 Which of these is NOT something that was traded during the Columbian Exchange? a university has decided to set aside 100 slots a year for minority applicants. which supreme court case ruling deemed such a policy unconstitutional? regents of the university of california v. bakke dowell v. oklahoma city mendez v. westminster plessy v. ferguson Mrs. Navarro has 36 students in her class, 16 boys and 20 girls.Select all ratios below that correctly describe the ratio of boys to girls in Mrs.Navarros's class. f(x) = 3x - 5x+20Find f(-8) there are no real boundaries for natural systems. explain how this applies to systems in the human body. explain why scientists establish boundaries for natural systems.