A box is sliding up an inclined plane with friction, and it is speeding up.What free-body diagrams matches this description?

What is the input of energy for a device that provides 50 units of useful energy and has an efficiency of 0.55?

ki77a [65]

If that's the case, then

 50 units = 0.55 x the input energy

Divide each side by 0.55 :

 50 units/0.55 = the input energy =

 90 and 10/11 units

3 0

3 years ago

What can be correctly concluded from this experiment?

solong [7]

1

Step by step explanation: 1

Brainlist?????

5 0

3 years ago

Read 2 more answers

A 20-kg block is held at rest on the inclined slope by a peg. A 2-kg pendulum starts at rest in a horizontal position when it is

gregori [183]

Complete Question

The diagram of this question is shown on the first uploaded image

Answer:

The distance the block slides before stopping is $d = 0.313 \ m$

Explanation:

The free body diagram for the diagram in the question is shown

From the diagram the angle is $\theta = 25 ^o$

$sin \theta = \frac{h}{d}$

Where $h = h_b - h_a$

So $d sin \theta = h_b - h_a$

From the question we are told that

The mass of the block is $m = 20 \ kg$

The mass of the pendulum is $m_p = 2 \ kg$

The velocity of the pendulum at the bottom of swing is $v_p = 15 m/s$

The coefficient of restitution is $e =0.7$

The coefficient of kinetic friction is $\mu _k = 0.5$

The velocity of the block after the impact is mathematically represented as

$v_2 f = \frac{m_b - em_p}{m_b + m_p} * v_2 i + \frac{[1 + e] m_1}{m_1 + m_2 } v_p$

Where $v_2 i$ is the velocity of the block before collision which is 0

$= \frac{20 - (0.7 * 2)}{(2 + 20)} * 0 + \frac{(1 + 0.7) * 2 }{2 + 20} * 15$

Substituting value

$v_2 f = 2.310\ m/s$

According to conservation of energy principle

The energy at point a = energy at point b

So $PE_A + KE _A = PE_B + KE_B + E_F$

Where

$PE_A$ is the potential energy at A which is mathematically represented as

$PE_A = m_b gh_a$ = 0 at the bottom

$KE _A$ is the kinetic energy at A which is mathematically represented as

$K_A = \frac{1}{2} m_b * v_2f^2$

$PE_B$ is the potential energy at B which is mathematically represented as

$PE_B = m_b gh$

From the diagram $h = h_b -h_a$

$PE_B = m_b g(h_b - h_a)$

$KE _B$ is the kinetic energy at B which is 0 (at the top )

Where is $E_F$ is the workdone against velocity which from the diagram is

$\mu_k m_b g cos 25 *d$

So

$\frac{1}{2} m_b v_2 f^2 = m_b g h_b + \mu_k m_b g cos \25 * d$

Substituting values

$\frac{1}{2} * 20 * 2.310^2 = 20 * 9.8 * d sin(25) + 0.5* 20 * 9.8 * cos 25 * d$

So

$d = 0.313 \ m$

6 0

3 years ago

A scientist adds different amounts of salt to 5 bottles of water. He then measures how long it takes for the water to boil. what

g100num [7]

The dependent variable is the amount of time it takes for the water to boil. This variable is dependent because is depends on the amount of salt.

4 0

3 years ago

Please help me on 3,4 and 6. Thanks

rusak2 [61]

3. The second piston will experience the same force as compared with the first. This is because since the pressure is the same everywhere inside the fluid system, the force is proportional to the surface area. We are told that both the first and the second piston have the same surface area, therefore, they will both experience the same force/pressure.

4. The situation is much the same as number 3 above, with the exception that the second piston is twenty times larger than the first. Again, since the pressure is the same everywhere inside the fluid system, the force is proportional to the surface area. We are told that the second piston is 20 times larger than the first, therefore, the larger piston will experience 20 times larger the force of the small one.

6. The answer is TRUE. The hydraulic braking system of most cars makes use of a vacuum servo (or booster), which is located between the brake pedal and the master cylinder piston. This vacuum servo amplifies the force applied from the brake pedal.

3 0

4 years ago