A block of mass 2 kg is placed on the floor. The coefficient of static friction is 0.4. A horizontal force of 2.5 N is applied on the block. Calculate the force of friction between the block and the floor.​

Explanation:

If Team A is on the left, B is on the right

if the force is constant, it means that the effort applied is equal.

So Team B is pulling 5000N to the right.

Answer:

C.25km

Explanation:

half of 50 is 25.

Answer:

C. 25 km

Explanation:

The train moves 50 kilometers in 1 hour.

In 0.5 hours, the train will travel 50(0.5) = 25 kilometers.

Answer:

  D. 3.0 × 10^-6 m

Explanation:

Wavelength is found by dividing the speed of light by the frequency:

  λ = c/f = (3·10^8 m/s)/(1.0·10^14 Hz) = 3.0·10^-6 m

Answer:

the main cause of decreasingthe efficient of simple machine is the effect of friction so, indoder to increase efficiency of a simple machine we should remove the friction using lubricants, decreasing the overload in machine,replacing sliding friction with rolling friction etc,

we should do thses all to increase efficiency of a simple machine.

hope u get it..

Explanation:

[tex]a = \frac{change \: in \: velocity}{change \: in \: time} [/tex]

[tex]a = \frac{v - u}{t} [/tex]

[tex]v = 7 {ms}^{ - 1} [/tex]

[tex]u = 15 {ms}^{ - 1} [/tex]

[tex]t = 3 \: seconds[/tex]

[tex]a = \frac{7 - 15}{3} [/tex]

[tex]a = \frac{ - 8}{3} [/tex]

[tex]a = - 2.67 \: {ms}^{ - 2} [/tex]

Answer:

15 m

Explanation:

The distance travelled by the driver before they put their foot on the brakes can be derived from the stopping distance and the braking distance of the car.

d = stopping distance - braking distance

Stopping distance = 50 m

Braking distance = 35 m

d = 50 - 35 m

d = 15 m

The distance travelled by the driver before they put their foot on the brakes is 15 m

Answer:

By nuclear fission

Explanation:

The sun generates enormous energy through the process of nuclear fusion.

The core or the innermost part of the sun is characterized by high temperature and pressure. These two factors cause the separation of nuclei from electrons and the fusion of hydrogen nuclei to form a  helium atom.

During the fusion process, energy is released.

Answer: In the direction of the first car.

Explanation:

Let the initial velocity of the first car be equal to U1 and the initial velocity of the second car be equal to U2

Given that the car is travelling with a positive velocity, and after it collides with another car moving with a negative velocity, the momentum before collision will be

M1U1 - M2U2

If the first car is still moving with a positive velocity, the second car will also be moving in the direction of the first car if the collision is inelastic collision.

Therefore, the direction of the second car will be positive direction if the collision is inelastic collision.

Answer:

decrease

Explanation:

as the mass of the cart increase the acceleration of the cart decrease

Given that,

Weight = 0.75 N

Acceleration due to gravity = 9.81 m/s²

Density of water = 1 g/ml

We need to calculate the volume of water

Using formula of weight

[tex]W=mg[/tex]

[tex]W=\rho Vg[/tex]

[tex]mg=\rho\times V\times g[/tex]

Where, V = volume

g = acceleration

m = mass

Put the value into the formula

[tex]0.076\times 9.8\times10^3=1\times V\times9.8[/tex]

[tex]V= \dfrac{0.076\times 9.8\times10^3}{1\times9.8}[/tex]

[tex]V=76\ ml[/tex]

Hence, The volume of water is 76 mL.

Answer:

76.5mL

Explanation:

w = mg

0.75N = m * 9.81

m = 0.75 / 9.81 = 0.0765 kg

The mass in grams is 0.0765 * 1000 = 76.5g

At a density of 1 g/mL,

76.5g ÷ 1g/ml = 76.5mL

Answer: The x-component of the total force 97N

Explanation:

Given the following :

Mass (M) of skier = 73.9 kg

Pull force on the skier = 105N

Angle of pull = 22.5°

The direct backward force directly pulling the skier = 74.8N

the x-component of the total force on the skier

The horizontal component of the force = Magnitude of the pulling force × cosine of the angle of pull (FCosΘ)

FCosΘ = 105cos22.5°

105cos22.5 = 105 × 0.9238795

= 97.007350

= 97N

The backward force acting directly backward = 74.8N

Therefore, net x - component of the total force equals ;

97N - 74.8N = 22.2N

Show us the experiment then

Answer:

i took g = 9.8m/s

A. 1.16secs

B. 2.32secs

C. 6.57m

D. 57.91m

Explanation:

A. How long does the Missile take to reach ot peak?

Time taken (t) =( U²Sin (angle) )/g

u = initial velocity = 25m/s

angle given = 30°

g = acceleration due to gravity = 9.8m/s²

t = U² x Sin (angle) / g

t = 25² x Sin(30)/9.8

t = 1.61secs

B. How long is the missile in the air in total?

T = 2t

T = 2 x 1.61 = 2.32 secs

C. what maximum Height does the missile reach?

D. How far does the missile travel Horizontally?

Answer: B. Carbon dioxide and water

Explanation: Combustion simply refers to burning. A combustion reaction may thus be explained as a chemical process which involves the reaction between a substance and an oxidizer usually oxygen gas. The combustion reaction in most cases involves the reaction between hydrocarbons which are combustible compounds and oxygen gas. The reaction between the combustible compound and oxygen gas is then followed by the release of energy, with the product being carbondioxid and water. Below is an example of combustion reaction.

Combustion the Methane CH4.

Here, CH4 reacts with oxygen gas(O2) to produce carbondioxide and water.

CH4 + 2O2 ------> CO2 + 2H2O

Answer:

Correct answer B

Explanation:

Just took quiz

Answer:

86.17m/s

Explanation:

Since the motion is of constant acceleration, we can use one of the equations of motion as follows;

v² = u² + 2as

Where;

v = final velocity of the airplane

u = initial velocity of the airplane

s = distance covered by the plane

a = acceleration

From the question,

u = 15m/s

s = 600m

a = 6m/s²

Substitute these values into the equation above as follows;

v² = 15² + 2(6)(600)

v² = 225 + 7200

v² = 7425

v = √7425

v  = 86.17m/s

Therefore, the final velocity of the airplane is 86.17m/s

Answer:

V = 0.01(R₁ + R₂)

Explanation:

From Ohm's law, the voltage V across a resistor with resistance R and a current I passing through it is given by

V = IR

If we have two resistances, R₁ and R₂ in series, the total resistance R is the sum of their resistances.

So, R = R₁ + R₂

Now, if the current in the circuit is 0.01 A, the voltage V is

V = IR

V = 0.01R

Substituting R = R₁ + R₂ into the equation for V, we have

V = 0.01(R₁ + R₂)

So, the voltage in two series resistors with current 0.01 A is

V = 0.01(R₁ + R₂)

Answer: The final Velocity, V, of the car is 7.9m/s

Explanation:

Given the following :

Toy car starts from rest, therefore,

Initial Velocity (u) = 0

Acceleration (a) = 1.5m/s^2 E for time, t = 5.25s

Final velocity (V) of the car =?

Using the motion equation:

v = u + at

Where v = final Velocity

u = Initial Velocity

a = acceleration

t = time

v = 0 + 1.5(5.25)

v = 0 + 7.875

v = 7.875m/s

v = 7.9m/s

Answer:

b

Explanation:

Light bends away from the normal, because it's moving from higher to lower refractive index.

Same bend-direction as when it goes from water into air.

Given that,

Frequency = 100 Hz

Velocity = 20 m/s

Suppose, Determinar la diferencia de  frecuencia entre la onda que recibe el observador directamente de la sirena y la onda que le llega reflejada  en el acantilado.

We need to calculate the frequency heard by the observer directly from source

Using formula of frequency

[tex]f_{1}=f\times(\dfrac{v}{v-v_{s}})[/tex]

Where, v = speed of sound

[tex]v_{s}[/tex] = speed of source

f = frequency of source

Put the value into the formula

[tex]f_{1}=100\times\dfrac{340}{340-20}[/tex]

[tex]f_{1}=106.25\ Hz[/tex]

We need to calculate the frequency heard by the observer coming after reflection from cliff

Using formula of frequency

[tex]f_{2}=f\times(\dfrac{v}{v+v_{s}})[/tex]

Put the value into the formula

[tex]f_{2}=100\times\dfrac{340}{340+20}[/tex]

[tex]f_{2}=94.4\ Hz[/tex]

We need to calculate the difference of  frequency

Using formula for difference of  frequency

[tex]\Delta f=f_{1}-f_{2}[/tex]

Put the value into the formula

[tex]\Delta f=106.25-94.4[/tex]

[tex]\Delta f=11.85\ Hz[/tex]

Hence, The difference of frequency is 11.85 Hz.

Answer:

Joule

Explanation:

As any unit of energy (kinetic, potential, etc.), the gravitational potential energy has SI units of Joule. This s the work done by a force of 1 Newton to displace an object 1 meter in the direction of application of the force.

Answer:

1.01 W/m

Explanation:

diameter of the pipe d = 30 mm = 0.03 m

radius of the pipe r = d/2 = 0.015 m

external air temperature Ta = 20 °C

temperature of pipe wall Tw = 150 °C

convection coefficient at outer tube surface h = 11 W/m^2-K

From the above, we assumed that the pipe wall and the oil are in thermal equilibrium.

area of the pipe per unit length A = [tex]\pi r ^{2}[/tex] = [tex]7.069*10^{-4}[/tex] m^2/m

convectional heat loss Q = Ah(Tw - Ta)

Q = 7.069 x 10^-4 x 11 x (150 - 20)

Q = 7.069 x 10^-4 x 11 x 130 = 1.01 W/m

The heat loss per unit length of tube should be considered as the 1.01 W/m.

Since

diameter of the pipe d = 30 mm = 0.03 m

radius of the pipe r = d/2 = 0.015 m

external air temperature Ta = 20 °C

temperature of pipe wall Tw = 150 °C

convection coefficient at outer tube surface h = 11 W/m^2-K

Now

area of the pipe per unit length A should be

= πr^2

 = 7.069*10^-4 m^2/m

Now

convectional heat loss Q = Ah(Tw - Ta)

Q = 7.069 x 10^-4 x 11 x (150 - 20)

Q = 7.069 x 10^-4 x 11 x 130

= 1.01 W/m

hence, The heat loss per unit length of tube should be considered as the 1.01 W/m.

Learn more about heat here: https://brainly.com/question/15170783

Copper is a reddish orange, soft metal with a bright metallic luster. It is an excellent conductor of heat and electricity. Copper surfaces when exposed to air gradually turns to a dull, brownish color.

Answer:

Explanation:

Kinetic energy is 1/2mv²

where m is the mass of the object

v is the velocity

From the question

m = 200kg

v = 2.7m/s

Kinetic energy is

1/2 × 200 × 2.7²

= 729 Joules

Hope this helps you

Answer:

Option A - Because of Newton's first law of motion

Explanation:

This is as a result of Newton's first law of motion.

Newton's first law of motion which is also referred to as the law of inertia states that; an object at rest will remain at rest and an object in motion will remain in motion with the same speed and in the same direction unless it's acted upon by an unbalanced force.

In this question, the car is at rest and it doesn't move because the upward force of the car is balanced by the downward pull of gravity. It can only move when an external force is applied to it. This fulfills Newton's first law of motion.

Answer:

I = 2.61 A

Explanation:

It is given that,

Power of a toaster is 300 watts

It is plugged into an outlet with a voltage of 115 volts

We need to find the current in the toaster's circuit.

The electrical power is given by the formula as follows :

P = V I

I is electric current

[tex]I=\dfrac{P}{V}\\\\I=\dfrac{300}{115}\\\\I=2.61\ A[/tex]

So, 2.61 A of current is in the toaster's circuit.

Answer: D.

2.61 amps

Explanation: edmentum

Answer:

n = 3.1x10¹²

Explanation:

To find the number of electrons we need to find first the charge (q):

[tex] I = \frac{q}{\Delta t} \rightarrow q = I*\Delta t [/tex]    (1)

Where:

I: is the electric current = 0.59 A

t: is the time

The time t is equal to:

[tex]v = \frac{\Delta x}{\Delta t} \rightarrow \Delta t = \frac{\Delta x}{v}[/tex]   (2)

Where:

x: is the displacement

v: is the average speed = 2.998x10⁸ m/s

The displacement is equal to the perimeter of the circumference:

[tex] \Delta x = 2\pi*r = \pi*d [/tex]     (3)

Where d is the diameter = 80.0 m

By entering equations (2) and (3) into (1) we have:

[tex]q = I*\Delta t = I*\frac{\Delta x}{v} = \frac{I\pi d}{v} = \frac{0.59 A*\pi*80.0 m}{2.99 \cdot 10^{8} m/s} = 4.96 \cdot 10^{-7} C[/tex]      

Now, the number of electrons (n) is given by:

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

Where e is the electron's charge = 1.6x10⁻¹⁹ C  

[tex] n = \frac{q}{e} = \frac{4.96 \cdot 10^{-7} C}{1.6 \cdot 10^{-19} C} = 3.1 \cdot 10^{12} [/tex]

Therefore, the number of electrons in the beam is 3.1x10¹².

I hope it helps you!

This question is incomplete because the options are missing; here is the complete question:

Study the image of the Earth's layer which statement correctly compares the thicknesses of earths layers

A. Earth’s mantle is thinner than its oceanic crust.

B. Earth’s outer core is thicker than its mantle.

C. Earth’s continental crust is thicker than its lithosphere.

D. Earth’s lithosphere is thinner than its asthenosphere.

The answer to this question is D. Earth’s lithosphere is thinner than its asthenosphere.

Explanation:

The image shows the different layers that are part of Earth, as well as the thickness of each layer, in kilometers. In this, the thickest layer is the Mantle that is almost 2900 kilometers; this is followed in thickness by the outer and the inner core.

Additionally, other layers such as the continental/oceanic crust, the asthenosphere, and the lithosphere that are near the surface are thinner. About this, it can be concluded the lithosphere is thinner than the asthenosphere because the lithosphere has a thickness of 100 km, while the asthenosphere thickness is 660km. This makes option D the correct.

Answer:

49 m/s

Explanation:

This is the question from the document:

1. A bag dropped from a helicopter falls with an acceleration of 9.8m/s2. What is its velocity after 5s?

We can find the answer by using the equation a = (v-u) / t

Acceleration a = 9.81m/s2

initial velocity u = 0 m/s (the bag is only dropped, so there's no initial velocity already existing)

time t= 5s

final velocity v = unknown

9.8 = (v -0) / 5

v - 0 = 9.8x5

v = 49 m/s