Answer:
Distance s = 90 meter
Explanation:
Given:
Initial velocity u = 0 m/s
Final velocity v = 30 m/s
Acceleration a = 5 m/s²
Find:
Distance s
Computation:
v² = u² + 2as
30² = 0² + 2(5)(s)
Distance s = 90 meter
A woman of mass 50 kg is swimming with a velocity of 1.6 m/s. If she stops stroking and glides to a stop in the water, what is the impulse of the force that stops her?
Answer:
Impulse of force = -80 Ns
Explanation:
Given the following data;
Mass = 50kg
Initial velocity = 1.6m/s
Since she glides to a stop, her final velocity equals to zero (0).
Now, we would find the change in velocity.
[tex] Change \; in \; velocity = final \; velocity - initial \; velocity [/tex]
Substituting into the equation above;
Change in velocity = 0 - 1.6 = 1.6m/s
[tex] Impulse \; of \; force = mass * change \; in \; velocity [/tex]
Substituting into the equation, we have;
[tex] Impulse \; of \; force = 50 * -1.6[/tex]
Impulse of force = -80 Ns
Therefore, the impulse of the force that stops her is -80 Newton-seconds and it has a negative value because it is working in an opposite direction, thus, bringing her to a stop.
What is the daily use of the deltoid?
Answer:
In our everyday life, the deltoids take on most of the work in rotating our arms, but besides that the deltoid muscle also allows us to carry objects at a safe distance from the body. It is also responsible from stopping a dislocation or injury to the humerus when we carry something heavy.
Answer:
Lifting, pushing and pulling
Explanation:
it uses it
A tennis ball moves 16 meters northward, then 22 meters southward, then 12 meters northward, and finally 32 meters southward.
Determine the magnitude of the distance the object traveled
Answer:
26 m southwards.
Explanation:
From a North, East, South, West coordinate plane, moving northwards implies positive distance. While moving southwards implies negative distance.
Thus;
It moves 16 meters northward; d = 16 m
It now moves 22 meters southward; d = -22 m
It moves 12 meters northward; d = 12 m
It moves 32 meters southward; d = -32 m
Thus, total magnitude = 16 - 22 + 12 - 32 = -26 m
Thus, the object travels 26 m southwards.
A ship's boiler steam comes out at 112 C and pushes through the system, exiting into the condenser,
which is kept at 20 C by circulating seawater. What is the ideal efficiency of the ship's boiler? Round to
the nearest thousandth.
O 0.643
O 0.523
O 0.703
O 0.239
Answer:
D: 0.239
Explanation:
Equation for ideal efficiency is;
η = 1 - (T_c/T_h)
We are told that;
steam comes out at 112° C. Thus, T_h = 112°C. Converting to Kelvin gives; T_h = 112 + 273 = 385 K
The one exiting into the condenser is kept at 20°C. Thus; T_c = 20 + 273 = 293 K
Thus;
η = 1 - (293/385)
η = 0.239
1. Which of the following will be surrounded by a magnetic field? *
1Two copper wires held close together.
2A pot being heated on an electric stove.
3A wire that is conducting an electrical current.
4An aluminum rod that has been touched by a magnet.
Answer:
4th answer
Explanation:
At t = 0, a car registers at 30 miles/hr. Forty seconds later, the car’s velocity is now at 50 miles/hr. Assuming constant acceleration, what is the distance covered after 40s?
Select one:
a. 0.442 mi
b. .33 mi
c. 0.11 mi
d. 10.33
e. None of the choices given.
Answer: Choice A) 0.44 miles
=================================================
Work Shown:
1 hour = 60 minutes
1 minute = 60 seconds
1 hour = 60*60 = 3600 seconds
40 seconds = 40*(1/3600) = 40/3600 = 1/90 hours
The car travels 1/90 of an hour. Let t = 1/90.
The initial velocity is vi = 30 mph.
The final velocity is vf = 50 mph.
Apply one of the kinematics equations as given below.
x = distance traveled
x = 0.5*(vi+vf)*t
x = 0.5*(30+50)*(1/90)
x = 0.44444444444444 which is approximate
x = 0.44
The car traveled roughly 0.44 miles. This matches with choice A.
I'm assuming choice A is supposed to say 0.44 instead of 0.442; otherwise, I think your teacher made a typo by putting that 2 in there. Each of the other answer choices are accurate to 2 decimal places, so it would make sense that choice A is also accurate to 2 decimal places as well.
If 0.442 was intended by your teacher, and it's not a typo, then the answer would be E) None of the choices given.
Kraig pulls a box to the right at an angle of 40 degrees to the horizontal with a force of 30 Newtons. If Kraig pulls the box a distance of 20 meters, determine the work done by Kraig.
Answer:
459.6J
Explanation:
Given parameters:
Angle of pull = 40°
Force applied = 30N
Distance moved = 20m
Unknown:
Work done by Kraig = ?
Solution:
To solve this problem;
Work done = F x dcosФ
d is the distance
F is the force
Ф is the angle given
Work done = 30 x 20cos40° = 459.6J
What allows a star to remain in stellar equilibrium?
Explanation:
A star is in equilibrium when the pressures inside the star balance out the force of gravity. The pressure is thermal pressure resulting from the fusion reactions taking place in the star's core. A star stays in equilibrium until the supply of hydrogen in the core is depleted.
In a stable star, the gas pressure pushing out from the center is equal with the gravity pulling atoms inward to the center – when these forces are equal, the star is at equilibrium. Once a star reaches equilibrium for the first time, it will start burning (fusing) hydrogen into helium.
Answer: It has enough mass to resist expansion.
You're driving your new sports car at 80 mph over the top of a hill that has a radius of curvature of 540 m. What fraction of your normal weight is your apparent weight as you crest the hill?
Answer:
75.84%
Explanation:
We were given Speed of the sports car, v as 80 mph , we can convert to m/s for unit consistency.
v=80mph= 35.76 m/s
The radius of curvature is given as , r = 540 m
✓ the normal weight can be denoted as Wn
✓ the apparent weight of the person can be denoted as Wa
Wn= normal weight= mg
Wa=apparent weight = (mg - mv^2/r)
g= acceleration due to gravity= 9.8m/s^2
The apparent weightand normal weight has a ratio of
Mn/Ma= [mg - mv^2/r]/mg ........eqn(1)
If we simplify eqn(1) we have
Mn/Ma=[g - vr^2/g].............eqn(2)
Then substitute the given values
Mn/Ma=9.8 - [(35.76^2)/540]/ 9.8
=0.758×100%
Mn/Ma=75.84%
Hence, the required fraction is 75.84%
Every force has a specific and identifiable cause called a(n)...............
1- agent
2- vector
3- system
4- direction
1. Calculate the heat capacity of a piece of wood if 1500.0 g of the wood absorbs 6.750.000 joules of heat,
and its temperature changes from 32°C to 57°C.
Answer:
1.8 J/gºC
Explanation:
From the question given above, the following data were obtained:
Mass (M) = 1500 g
Heat (Q) absorbed = 67500 J
Initial temperature (T₁) = 32 °C
Final temperature (T₂) = 57 °C
Specific heat capacity (C) =?
Next, we shall determine the change in temperature of the wood. This can be obtained as follow:
Initial temperature (T₁) = 32 °C
Final temperature (T₂) = 57 °C
Change in temperature (ΔT) =.?
ΔT = T₂ – T₁
ΔT = 57 – 32
ΔT = 25 °C
Finally, we shall determine the heat capacity of the wood. This can be obtained as follow:
Mass (M) = 1500 g
Heat (Q) absorbed = 67500 J
Change in temperature (ΔT) = 25 °C
Specific heat capacity (C) =?
Q = MCΔT
67500 = 1500 × C × 25
67500 = 37500 × C
Divide both side by 37500
C = 67500 / 37500
C = 1.8 J/gºC
Thus, the heat capacity of the wood is 1.8 J/gºC
The ball of a ballpoint pen is 0.5 mm in diameter and has an ASTM grain size of 12. How many grainsare there in the ball
Answer:
the number of grains in the ball is 274,848
Explanation:
Given that;
diameter = 0.5 mm
so radius r = 0.25 mm
first we determine the volume of the ball using the following equation;
V = 4/3×πr³
we substitute
V = 4/3×π(0.25)³
V = 0.06544 mm³
Now form table 1.1 "Grain sizes" a metal with grain size number of 12 has about 4,200,000 grains/mm³
so;
Number of grains N = 0.06544 × 4,200,000
N = 274,848 grains
Therefore, the number of grains in the ball is 274,848
A drone is flying horizontally when it runs out of power and begins to free fall from 16 m. No drag. If it lands 40 m away (in the x-direction) from where it began to fall, what was its horizontal velocity while it was falling
Answer:
the horizontal velocity while it was falling is 22.1 m/s.
Explanation:
Given;
height of fall, h = 16 m
horizontal distance, x = 40 m
The time to travel 16 m is calculated as;
[tex]t = \sqrt{\frac{2h}{g} } \\\\t = \sqrt{\frac{2\times 16}{9.8} } \\\\t = 1.81 \ s[/tex]
The horizontal velocity is calculated as;
[tex]v_x = \frac{X}{t} \\\\v_x = \frac{40}{1.81} \\\\v_x = 22.1 \ m/s[/tex]
Therefore, the horizontal velocity while it was falling is 22.1 m/s.
The horizontal velocity while it was falling is
[tex]22.1m/s[/tex]What is horizontal velocity?Horizontal velocity becomes important for objects moving in a horizontal direction. Generally, horizontal velocity is horizontal displacement divided by time, such as mph or m/s.
Therefore, from equation of motion
[tex]Time, t = \sqrt\frac{2h}{g}\\\\t = \sqrt\frac{2*16}{9.8}\\\\t = 1.81sec[/tex]
Therefore, the horizontal velocity, [tex]V_h[/tex]
[tex]V_h = \frac{x}{t}\\\\V_h = \frac{40}{1.81}\\\\V_h = 22.09 or 22.1m/s[/tex]
For more information on horizontal velocity, visit
https://brainly.com/question/24681896
What surprises you about ancient belief systems about the age of the universe?
A plot of land contains 3.6 acres. How many square meters does it contain? [1 acre = 43,560 ft?)
Answer:
It contains approximately 14,568.7 square meters
Explanation:
Area Units Conversion
There are several units to express the area of a shape:
[tex]cm^2,\ m^2,\ km^2,\ ft^2,\ in^2,\ acres, \ hectares[/tex]
The process of expressing the area from one unit to the other is called a conversion.
Specifically, we are interested in converting from acres to square meters. The rule to make the conversion is:
[tex]1 acre = 4,046.86\ m^2[/tex]
The plot of land has 3.6 acres, thus its area is:
[tex]3.6 * 4046.86 =14,568.696\ m^2[/tex]
It contains approximately 14,568.7 square meters
21. Which substance is a gas at 45 degrees C?* A. Ethanol O B. Hexane C. Methane O D. Methanol
Answer:
C. Methane
Explanation:
A chemical equation can be defined as a reaction between two chemical elements.
For a chemical reaction (equation) to be balanced, the condition which must be met is that the number of atoms contained in the reactants must be equal to the number of atoms in the products.
This ultimately implies that, the mass and charge of the chemical equation are both balanced properly.
Methane is a hydrocarbon compound formed by the reaction between four (4) hydrogen atoms with a carbon atom. It belongs to the alkane group of hydrocarbons and has the following physical and chemical properties; colorless, highly flammable, non-toxic and odorless gas. The empirical formula for Methane is CH4.
Methane is a gas at 45 degrees celsius. This ultimately implies that, at 45°C methane is a gas because it is still within the range of standard temperature and pressure.
Suppose you have a total charge qtot that you can split in any manner. Once split, the separation distance is fixed. How do you split the charge to achieve the greatest force
Answer:
Answer is explained in the explanation section below.
Explanation:
Solution:
We know from the Coulomb's Law that, Coulomb's force is directly proportional to the product of two charges q1 and q2 and inversely proportional to the square of the radius between them.
So,
F = [tex]\frac{Kq1q2}{r^{2} }[/tex]
Now, we are asked to get the greatest force. So, in order to do that, product of the charges must be greatest because the force and product of charges are directly proportional.
Let's suppose, q1 = q
So,
if q1 = q
then
q2 = Q-q
Product of Charges = q1 x q2
Now, it is:
Product of Charges = q x (Q-q)
So,
Product of Charges = qQ - [tex]q^{2}[/tex]
And the expression qQ - [tex]q^{2}[/tex] is clearly a quadratic expression. And clearly its roots are 0 and Q.
So, the highest value of the quadratic equation will be surely at mid-point between the two roots 0 and Q.
So, the midpoint is:
q = [tex]\frac{Q + 0}{2}[/tex]
q = Q/2 and it is the highest value of each charge in order to get the greatest force.
4. A driver takes 3.5 s to react to a complex situation. How far does the vehicle travel before the driver initiates a physical response to the situation (i.e., putting his or her foot on the brake)
This question is incomplete, the complete question is;
A driver takes 3.5 s to react to a complex situation while driving at a speed of 60 mi/h.
How far does the vehicle travel before the driver initiates a physical response to the situation (i.e., putting his or her foot on the brake)
Answer:
the distance travelled by the vehicle, before the driver initiates a physical response is 308 ft
Explanation:
Given that;
Reaction time t = 3.5 sec
Speed S = 60 mi/h
we convert mile to foot and hour to seconds
so
Speed S = 60 mi/h = (60×5280)/(60×60) = 316800/3600 = 88 ft/sec
Now, The distance travelled by vehicle before the driver initiates physical response is equal to Lag distance. i.e
Lag distance = V × t
we substitute
Lag distance = 88 ft/sec 3.5 sec
Lag distance = 308 ft
Therefore, the distance travelled by the vehicle, before the driver initiates a physical response is 308 ft
6. What is the complete spectrum of all forms of light?
a. galaxy
b. electromagnetic spectrum
C. energy
d. system
Answer:
b. the electromagnetic spectrum
Explanation:
the electromagnetic spectrum contains all the forms of light, including gamma rays, x-rays, ultraviolet radiation, visible light, infrared, radio waves, microwaves, etc
An engine has an output energy of 2,400 J in 10 seconds. What is its average power in watts?
Answer:
P = 240 W
Explanation:
By definition, the average power is the rate of change of Energy (in Joules) regarding time (in seconds), as follows:[tex]P = \frac{\Delta E}{\Delta t} (1)[/tex]
Replacing in (1) by the givens of ΔE = 2, 400 J and Δt = 10 sec, we can find the average power in Watts as follows:[tex]P = \frac{\Delta E}{\Delta t} =\frac{2,400J}{10s} = 240 W (2)[/tex]
Which is an example of convection currents?
marshmallows toasting over a campfire
a pot being heated by an electric burner
feet getting hot when stepping across sand
a radiator emitting warm air and drawing in cool air
Answer:
D
Explanation:
took the quiz!!! I picked B and got it wrong!
An example of convection currents is a radiator emitting warm air and drawing in cool air.
What is Convection?This is a method of heat transfer which is characterized by movement of a heated fluid such as air or water.
A radiator emitting warm air and drawing in cool air involves a fluid which is why option D was chosen as the most appropriate choice.
Read more about Convection here https://brainly.com/question/9382711
Moving a ball up a hill
O A. increases its chemical energy
OB. decreases its chemical energy
O C. increases its potential energy
OD. decreases its potential energy
Answer:
C increase in potential energy
A badminton shuttlecock leaves the racquet traveling 30 m/s. It goes over the net 0.5
seconds later with a speed of 10 m/s. Calculate its average acceleration.
Given :
A badminton shuttlecock leaves the racquet traveling 30 m/s.
It goes over the net 0.5 seconds later with a speed of 10 m/s.
To Find :
The average acceleration of the shuttlecock.
Solution :
We know, average acceleration(a) is given by :
[tex]a = \dfrac{\text{Change in speed}}{\text{Time taken }}\\\\a = \dfrac{10-30}{0.5 }\ m/s^2\\\\a = -40\ m/s^2[/tex]
Therefore, the average acceleration is -40 m/s².
The view of light that describes light as consisting of particles is called: Select the correct answer below: particulate spherical discrete corpuscular
Answer: Corpuscular.
Explanation:
There is a theory called the Corpuscular Theory of Light, which says that light is made of small particles called "corpuscles".
But as we know, light has a duality associated to it (it behaves like a wave and like a particle), and here is where one of the largest problems of this theory appears, because it does not explain things like diffraction or interference.
Then the correct option is corpuscular.
Answer:
hes right
Explanation:
A generator transforms?
A 800kg car produces a motive force of 10,000N.
As it accelerates from rest it experiences a frictional resistance of 2,000N.
What is the net force acting on the car?
Answer:
the net force on the car is 8,000 N.
Explanation:
Given;
mass of the car, m = 800 kg
motive force of the car, F = 10,000 N
frictional force experienced by the car, Fk = 2,000 N
The net force on the car is calculated as;
∑F = F - Fk
∑F = 10,000 - 2,000
∑F = 8,000 N
Therefore, the net force on the car is 8,000 N.
Determine the values of mm and nn when the following mass of the Earth is written in scientific notation: 5,970,000,000,000,000,000,000,000 kgkg.
Answer:
"m" and "n" are 5.97 and 24 respectively.
Explanation:
Standard form which is a scientific notation [m × 10^n] can be regarded as way to reduce large figures to small one in a decimal firm and this is usually done for conviniency sake.
✓Let us find "m" , to do this we will shorten the long number so that it will be from 1-9. And this is 5.97, hence
m = 5.97
✓ " n" can be determined by counting the digits from our right hand then stop where the decimal point was put when we were finding our "m". Hence
n= 24
✓ if we input the values to the scientific expresion above, we have
m = 5.97 and n = 24
Hence, the Standard form = 5.97 × 10^24 kg which is the scientific notation.
By experiment, determine what makes a force attractive or repulsive. Describe your experiments and observations with some examples. 4. What evidence do you see that Newton's third law applies to electrostatic forces
Answer:
he combs are brought closer, each one has to move, therefore a force must be applied to each one, and the only force is electrostatic. force must have the same magnitude in each one and in the opposite direction; this description is equivalent to Newton's third law.
Explanation:
A very simple experiment that we can do is to rub a brush or plastic comb with a piece of paper, this creates some electrical charges in the comb, we hang the comb by a thread.
We take another comb and we form it with the same paper, when we bring the combs closer, we see that they repel each other, this is proof that the electrical charges created are of the same type.
If now we rub the comb with another material, for example plastic, and bring it closer to the comb that is hanging, we see that they are approaching, therefore, it is proven that the load created from another type
With these two simple experiments it can be proved that electric charges are of two types, which are called positive and negative.
4. In the previous experiment we see that when the combs are brought closer, each one has to move, therefore a force must be applied to each one, and the only force is electrostatic. If we observe carefully we see that the breaking of the combs is the same, therefore the force must have the same magnitude in each one and in the opposite direction; this description is equivalent to Newton's third law.
What new details are you able to see on the slide when the magnification is increased to 10x that you could not see at 4x
Answer: A more detailed information like the nucleus of cells on the slide is seen as the magnification Increases.
Explanation:
The microscope is an instrument used in a laboratory to view magnified image of an object ( cells on a slide). There are two types:
--> Simple microscope and
--> Compound microscope.
Simple microscope is used to view an object using JUST ONE convex lens, and the image formed is usually erect and magnified.
Compound microscope has a higher magnification compared to a simple microscope. It is produced by using TWO CONVERGING LENS of short focal length. Here, the two lenses used are classified according to their positions. The lens near the object is called the objective lens while the one nearer to the eye is called the eyepiece lens.
The objective lens of the compound lens used in the laboratory has ×4, ×10, ×40, ×100 magnifications. As the magnification of the objective lens is increased from ×4 to ×10 a more detailed information of the image is seen as the diameter of field of view decreases. For example the constituents of a cell like the nucleus can be viewed using a higher magnification.
1. The directional movement of ions by facilitated diffusion through protein channels is determined by
Answer:
The electrochemical gradient of the ion that is being transported.
Explanation:
Facilitated diffusion through protein is defined as a form of facilitated transport whereby passive movement of ions along concentration gradients are guided by the presence of other ions.
Thus, the electrochemical gradient of the ion being transported is what facilitates it