A player caught a cricket ball of mass \(150\ \text{g}\) moving at a rate of \(20\ \text{m/s}\). If the catching process is completed in \(0.1\ \text{s}\), then the force of the blow exerted by the ball on the hands of the player is:

1. \(0.3\ \text{N}\)
2. \(30\ \text{N}\)
3. \(300\ \text{N}\)
4. \(3000\ \text{N}\)

Subtopic:  Newton's Laws |
 84%
Level 1: 80%+
PMT - 2001
Hints

A rocket of mass \(100\ \text{kg}\) ejects exhaust gases at a rate of \(1\ \text{kg/s}\) with a velocity of \(500\ \text{m/s}\) relative to the rocket. Neglecting external forces, the initial thrust produced by the rocket is:

1. Zero
2. \(500\ \text{N}\)
3. \(1000\ \text{N}\)
4. \(2000\ \text{N}\)

Subtopic:  Variable Mass System |
 78%
Level 2: 60%+
Hints

In which of the following cases will a force not be required to keep the particle in the given motion?
(A) The particle is going in a circle.
(B) The particle is moving in uniform straight-line motion.
(C) The momentum of the particle is constant.
(D) The acceleration of the particle is constant.

Choose the correct option from the given ones:
1. (A) and (B)
2. (A) and (D)
3. (B) and (C)
4. (C) and (D)

Subtopic:  Newton's Laws |
 59%
Level 3: 35%-60%
Hints

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A ball of mass \(150\ \text{g}\) starts moving with an acceleration of \(20\ \text{m/s}^2\) when hit by a force, which acts on it for \(0.1\ \text{s}\). The impulsive force is:

1. \(0.5\ \text{N-s}\)
2. \(0.1\ \text{N-s}\)
3. \(0.3\ \text{N-s}\)
4. \(1.2\ \text{N-s}\)

Subtopic:  Newton's Laws |
 90%
Level 1: 80%+
PMT - 2003
Hints

A body of constant mass has constant linear momentum. Which of the following quantities must remain constant? 

1. force.

2. velocity.

3. acceleration.

4. All of these

Subtopic:  Newton's Laws |
 61%
Level 2: 60%+
Hints

Rocket engines lift a rocket from the Earth's surface because hot gases with high velocity:

1. push against the Earth.

2. push against the air.

3. react against the rocket and push it up.

4. heat up the air, which lifts the rocket.

Subtopic:  Variable Mass System |
 56%
Level 3: 35%-60%
Hints

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A force of \(50\) dynes is applied to a body of mass \(5\ \text{g}\), which is at rest for an interval of \(3\) seconds; then the impulse is: 

1. \(0 .15 × 10^{-3}  \ \text{Ns}\)
2. \(0 .98 × 10^{-3}\ \text{N s}\)
3. \(1.5 × 10^{-3}\ \text{N s}\)
4. \(2.5 × 10^{-3}\ \text{N s}\)

Subtopic:  Newton's Laws |
 77%
Level 2: 60%+
Hints

A bullet of mass \(0.1\ \text{kg}\) is fired with a speed of \(100\ \text{m/s}\), the mass of the gun is \(50\ \text{kg}\). The velocity of recoil is:

1. \(0.2\ \text{m/s}\)
2. \(0.1\ \text{m/s}\)
3. \(0.5\ \text{m/s}\)
4. \(0.05\ \text{m/s}\)

Subtopic:  Newton's Laws |
 86%
Level 1: 80%+
PMT - 2002
Hints

Three forces start acting simultaneously on a particle moving with velocity \(\vec v\). These forces are represented in magnitude and direction by the three sides of a triangle \(ABC\) (as shown). The particle will now move with velocity:

1. \(\vec v\) remaining unchanged
2. Less than \(\vec v\)
3. Greater than \(\vec v\)
4. \(\vec v\) in the direction of the largest force \(BC\)

Subtopic:  Application of Laws |
 76%
Level 2: 60%+
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Two blocks of masses \(2\ \text{kg}\) and \(4\ \text{kg}\) are connected vertically by a light, inextensible string, as shown in the figure. The upper block is pulled upward by another string, causing both blocks to accelerate upward at \(2\ \text{m/s}^2\). If \(T\) and \(T’\) are the tensions in the upper and lower strings, respectively, the values of \(T\) and \(T’\) are:

1. \(T = 70.8\ \text{N}\ \text{and}\ T’ = 47.2\ \text{N}\)
2. \(T = 58.8\ \text{N}\ \text{and}\ T’ = 47.2\ \text{N}\)
3. \(T = 70.8\ \text{N}\ \text{and}\ T’ = 58.8\ \text{N}\)
4. \(T = 70.8\ \text{N}\ \text{and}\ T’ = 40.2\ \text{N}\)

Subtopic:  Application of Laws |
 68%
Level 2: 60%+
Hints