Velocity Ratio

Q. Explain briefly any three applications of Newton's second law of motion.

Q.

A machine has a velocity ratio of 4. It is used to raise a load of 200 N by 4 m using an effort of 20 kgf. Find the work done on the machine. Take $g=10m{s}^{-2}$​.

1. 1600 J

2. 3200 J

3. 6400 J

4. 2000 J

Q. Which one of the following cannot be explained on the basis of newton’s third law of motion?

1. Rowing of a boat in a pond
2. Motion of jet in the sky
3. Returning back of a body thrown above
4. Rebounding of a ball from a wall

Q.

What is the effect of force when a ball is hit with a bat ?

Q. A 50 g bullet pierces through a plate of mass M₁ = 1 kg and then comes to rest inside a second plate of mass M₂ = 2.95 kg as shown in figure. It is found that the two plates, initially at rest, now move with equal velocities. Find the percentage loss in the initial velocity of bullet when it is between M₁ and M₂. (Neglect any loss of material of the plates due to the action of the bullet.)

50 g की एक गोली द्रव्यमान M₁ = 1 kg की प्लेट में छेद करते हुए इससे गुजरती है तथा फिर चित्रानुसार द्रव्यमान M₂ = 2.95 kg की द्वितीय प्लेट के अंदर विराम में आती है। यह पाया जाता है कि प्रारम्भ में विराम में स्थित दोनों प्लेटें अब समान वेगों से गति करती हैं। जब गोली M₁ व M₂ के मध्य हैं, तब गोली के प्रारम्भिक वेग में प्रतिशत हानि ज्ञात कीजिए। (गोली की क्रिया के कारण प्लेटों के पदार्थ में किसी भी हानि को नगण्य मानिए।)

1. 50%
2. 25%
3. 75%
4. 20%

Q. A water tanker filled up to $\frac{2}{3}$rd of its height is moving with a uniform speed. On sudden application of the brake, the water in the tank would

1. move backward
2. move forward
3. be unaffected
4. move sidewards

Q. Newton’s third law of motion states that for every action, there is an equal and opposite reaction. Which of the following statements can be inferred from the above-mentioned law of motion?
Statement 1: For every interaction, there is a pair of forces acting on the two interacting objects.
Statement 2: The magnitude of the force on the first object equals the magnitude of the force on the second object.
Statement 3: Forces always come in pairs - equal and opposite action-reaction force pairs.
Statement 4: Action and its reaction act on the same bodies.
Statement 5: Action and its reaction act on two different bodies.

1. All statements except 4 can be inferred from $3^{rd}$ law of motion
2. Only statement 1 can be inferred from $3^{rd}$ law of motion
3. All statements except 5 can be inferred from $3^{rd}$ law of motion
4. All statements can be inferred from $3^{rd}$ law of motion

Q.

What is velocity ratio? Does it have any unit.

Q.

Find the scalar and vector from the following speed, distance, current, time, velocity, pressure , work done, Momentum and acceleration

Q. A person jumping out of a moving train tends to fall in the direction of the moving train. This is an example of inertia of motion.

1. True
2. False

Q.

We obtain a definition of the force from first law of motion and the measure of the force from second law of motion.

1. True
2. False

Q.

What is the expression for Velocity Ratio (V.R), if the velocity of effort and the velocity of the load are denoted as V1 and V2 respectively?

1. V2=V1

2. V1/V2

3. V2/V1

4. V1+V2=0

Q. Newton's first law qualitatively describes inertia.

1. False
2. True

Q. The rate at which the displacement of a body changes, is called velocity of the body.

1. True
2. False

Q.

The Efficiency(E) of any machine is given by:-

1. $E=\frac{\text{Work input}}{\text{Work output}}$

2. $E=\frac{\text{Work output}}{\text{Work~ input}}\text{or}E=\frac{\text{MA}}{\text{V.R.}}$

3. $E=\frac{\text{Effort}}{\text{Load}}$

4. $E=\frac{\text{V.R.}}{\text{MA}}$

Q. The product of the mass and the velocity of a body is termed as:

1. Acceleration
2. Force
3. Inertia
4. Momentum

Q.

The unit of Velocity Ratio is

1. m

2. No unit

3. None of these

4. $m^2$

Q.

When a car stops suddenly by applying force, why do the passengers sitting in it lean forward?

Q. The product of the mass and the velocity of a body is termed as:

1. Acceleration
2. Force
3. Inertia
4. Momentum

Q. Newton's first law qualitatively describes inertia.

1. True
2. False