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Laws of Motion

270136 $n$ balls each of mass $m$ impinge elastically in each second on a surface with velocity $u$ . The average force experienced by the surface will be

1

mnu

2

2 mnu

3

4 mnu

4

mnu / 2

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270137 A ball reaches a racket at $60 m / s$ along $+ X$ direction, and leaves the racket in the opposite direction with the same speed. Assuming that the mass of the ball as $50 gm$ and the contact time is 0.02 second, the force exerted by the racket on the ball is

1

300 N

along

+ X

direction

2

300 N

along -

X

direction

3

3, 00, 000 N

along

+ X

direction

4

3, 00, 000 N

along -

X

direction

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270138 ' $P$ ' and ' $Q$ ' horizontally push in the same direction a $1200 kg$ crate. ' $P$ ' pushes with a force of 500 newton and ' $Q$ ' pushes with a force of 300 newton. If a frictional force provides 200 newton of resistance, what is the acceleration of the crate?

1

1.3 m / s^{2}

2

1.0 m / s^{2}

3

0.75 m / s^{2}

4

0.5 m / s^{2}

Explanation:

$F_{net} = m a, a = \frac{F_{n e t}}{m} = \frac{(F_{p} + F_{Q}) - f}{m}$

Laws of Motion

270139 A ball of mass ' $m$ ' moves normal to a wall with a velocity ' $u$ ' and rebounds with a velocity ' $v$ '. The change in momentum of the ball during the rebounding is

1

m (u + v)

towards the wall

2

m (u - v)

towards the wall

3

m (u + v)

away from the wall

4

m (u - v)

away from the wall.

Explanation:

$Δ P = P_{f} - P_{i} = m (V - u)$

Laws of Motion

270140 If a force of $250 N$ acts on a body,the momentum required is $125 {kgms}^{- 1}$ . The period for which the force acts on the body is

1

0.1 s

2

0.3 s

3

0.5 s

4

0.2 s

Explanation:

$F = \frac{d p}{d t} \Rightarrow d t = \frac{d p}{F}$

Laws of Motion

270136 $n$ balls each of mass $m$ impinge elastically in each second on a surface with velocity $u$ . The average force experienced by the surface will be

1

mnu

2

2 mnu

3

4 mnu

4

mnu / 2

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270137 A ball reaches a racket at $60 m / s$ along $+ X$ direction, and leaves the racket in the opposite direction with the same speed. Assuming that the mass of the ball as $50 gm$ and the contact time is 0.02 second, the force exerted by the racket on the ball is

1

300 N

along

+ X

direction

2

300 N

along -

X

direction

3

3, 00, 000 N

along

+ X

direction

4

3, 00, 000 N

along -

X

direction

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270138 ' $P$ ' and ' $Q$ ' horizontally push in the same direction a $1200 kg$ crate. ' $P$ ' pushes with a force of 500 newton and ' $Q$ ' pushes with a force of 300 newton. If a frictional force provides 200 newton of resistance, what is the acceleration of the crate?

1

1.3 m / s^{2}

2

1.0 m / s^{2}

3

0.75 m / s^{2}

4

0.5 m / s^{2}

Explanation:

$F_{net} = m a, a = \frac{F_{n e t}}{m} = \frac{(F_{p} + F_{Q}) - f}{m}$

Laws of Motion

270139 A ball of mass ' $m$ ' moves normal to a wall with a velocity ' $u$ ' and rebounds with a velocity ' $v$ '. The change in momentum of the ball during the rebounding is

1

m (u + v)

towards the wall

2

m (u - v)

towards the wall

3

m (u + v)

away from the wall

4

m (u - v)

away from the wall.

Explanation:

$Δ P = P_{f} - P_{i} = m (V - u)$

Laws of Motion

270140 If a force of $250 N$ acts on a body,the momentum required is $125 {kgms}^{- 1}$ . The period for which the force acts on the body is

1

0.1 s

2

0.3 s

3

0.5 s

4

0.2 s

Explanation:

$F = \frac{d p}{d t} \Rightarrow d t = \frac{d p}{F}$

Laws of Motion

270136 $n$ balls each of mass $m$ impinge elastically in each second on a surface with velocity $u$ . The average force experienced by the surface will be

1

mnu

2

2 mnu

3

4 mnu

4

mnu / 2

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270137 A ball reaches a racket at $60 m / s$ along $+ X$ direction, and leaves the racket in the opposite direction with the same speed. Assuming that the mass of the ball as $50 gm$ and the contact time is 0.02 second, the force exerted by the racket on the ball is

1

300 N

along

+ X

direction

2

300 N

along -

X

direction

3

3, 00, 000 N

along

+ X

direction

4

3, 00, 000 N

along -

X

direction

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270138 ' $P$ ' and ' $Q$ ' horizontally push in the same direction a $1200 kg$ crate. ' $P$ ' pushes with a force of 500 newton and ' $Q$ ' pushes with a force of 300 newton. If a frictional force provides 200 newton of resistance, what is the acceleration of the crate?

1

1.3 m / s^{2}

2

1.0 m / s^{2}

3

0.75 m / s^{2}

4

0.5 m / s^{2}

Explanation:

$F_{net} = m a, a = \frac{F_{n e t}}{m} = \frac{(F_{p} + F_{Q}) - f}{m}$

Laws of Motion

270139 A ball of mass ' $m$ ' moves normal to a wall with a velocity ' $u$ ' and rebounds with a velocity ' $v$ '. The change in momentum of the ball during the rebounding is

1

m (u + v)

towards the wall

2

m (u - v)

towards the wall

3

m (u + v)

away from the wall

4

m (u - v)

away from the wall.

Explanation:

$Δ P = P_{f} - P_{i} = m (V - u)$

Laws of Motion

270140 If a force of $250 N$ acts on a body,the momentum required is $125 {kgms}^{- 1}$ . The period for which the force acts on the body is

1

0.1 s

2

0.3 s

3

0.5 s

4

0.2 s

Explanation:

$F = \frac{d p}{d t} \Rightarrow d t = \frac{d p}{F}$

Laws of Motion

270136 $n$ balls each of mass $m$ impinge elastically in each second on a surface with velocity $u$ . The average force experienced by the surface will be

1

mnu

2

2 mnu

3

4 mnu

4

mnu / 2

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270137 A ball reaches a racket at $60 m / s$ along $+ X$ direction, and leaves the racket in the opposite direction with the same speed. Assuming that the mass of the ball as $50 gm$ and the contact time is 0.02 second, the force exerted by the racket on the ball is

1

300 N

along

+ X

direction

2

300 N

along -

X

direction

3

3, 00, 000 N

along

+ X

direction

4

3, 00, 000 N

along -

X

direction

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270138 ' $P$ ' and ' $Q$ ' horizontally push in the same direction a $1200 kg$ crate. ' $P$ ' pushes with a force of 500 newton and ' $Q$ ' pushes with a force of 300 newton. If a frictional force provides 200 newton of resistance, what is the acceleration of the crate?

1

1.3 m / s^{2}

2

1.0 m / s^{2}

3

0.75 m / s^{2}

4

0.5 m / s^{2}

Explanation:

$F_{net} = m a, a = \frac{F_{n e t}}{m} = \frac{(F_{p} + F_{Q}) - f}{m}$

Laws of Motion

270139 A ball of mass ' $m$ ' moves normal to a wall with a velocity ' $u$ ' and rebounds with a velocity ' $v$ '. The change in momentum of the ball during the rebounding is

1

m (u + v)

towards the wall

2

m (u - v)

towards the wall

3

m (u + v)

away from the wall

4

m (u - v)

away from the wall.

Explanation:

$Δ P = P_{f} - P_{i} = m (V - u)$

Laws of Motion

270140 If a force of $250 N$ acts on a body,the momentum required is $125 {kgms}^{- 1}$ . The period for which the force acts on the body is

1

0.1 s

2

0.3 s

3

0.5 s

4

0.2 s

Explanation:

$F = \frac{d p}{d t} \Rightarrow d t = \frac{d p}{F}$

Laws of Motion

270136 $n$ balls each of mass $m$ impinge elastically in each second on a surface with velocity $u$ . The average force experienced by the surface will be

1

mnu

2

2 mnu

3

4 mnu

4

mnu / 2

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270137 A ball reaches a racket at $60 m / s$ along $+ X$ direction, and leaves the racket in the opposite direction with the same speed. Assuming that the mass of the ball as $50 gm$ and the contact time is 0.02 second, the force exerted by the racket on the ball is

1

300 N

along

+ X

direction

2

300 N

along -

X

direction

3

3, 00, 000 N

along

+ X

direction

4

3, 00, 000 N

along -

X

direction

Explanation:

$F_{avg} = m a, a = \frac{v - u}{t}$

Laws of Motion

270138 ' $P$ ' and ' $Q$ ' horizontally push in the same direction a $1200 kg$ crate. ' $P$ ' pushes with a force of 500 newton and ' $Q$ ' pushes with a force of 300 newton. If a frictional force provides 200 newton of resistance, what is the acceleration of the crate?

1

1.3 m / s^{2}

2

1.0 m / s^{2}

3

0.75 m / s^{2}

4

0.5 m / s^{2}

Explanation:

$F_{net} = m a, a = \frac{F_{n e t}}{m} = \frac{(F_{p} + F_{Q}) - f}{m}$

Laws of Motion

270139 A ball of mass ' $m$ ' moves normal to a wall with a velocity ' $u$ ' and rebounds with a velocity ' $v$ '. The change in momentum of the ball during the rebounding is

1

m (u + v)

towards the wall

2

m (u - v)

towards the wall

3

m (u + v)

away from the wall

4

m (u - v)

away from the wall.

Explanation:

$Δ P = P_{f} - P_{i} = m (V - u)$

Laws of Motion

270140 If a force of $250 N$ acts on a body,the momentum required is $125 {kgms}^{- 1}$ . The period for which the force acts on the body is

1

0.1 s

2

0.3 s

3

0.5 s

4

0.2 s

Explanation:

$F = \frac{d p}{d t} \Rightarrow d t = \frac{d p}{F}$