EASY
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Change of momentum and rate of change of momentum are the same.

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Important Questions on Laws of Motion

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An object of mass 10 gm is moving with an acceleration of 10 m/s2. Force acting on the object will be:
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In a two body collision, the momentum is varying with time as shown in graph. The instantaneous force is maximum at: 

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EASY

The variation in momentum with time, for a body under collision is shown in figure. The maximum & minimum instantaneous forces are respectively on these points:

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EASY

Read the following statements and choose the correct option:
Statement: Newton's second law of motion gives the measurement of force. 
Reason: According to Newton's second law of motion, force is directly proportional to the rate of change of momentum. 

MEDIUM
Figure shows the velocity versus time graph for a block of mass 50 g sliding on a rough floor. The average rate at which energy dissipates (in Js-1) due to the force of friction is:  
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MEDIUM

The velocity-time graph of a ball of mass 20 g moving along a straight line on a long table is given in figure.The force exerted by the table on the ball to bring it to rest is :

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EASY

A force ‘F’ is applied on one end of a rope of length ‘a’. P and Q are two points of length ‘b’ from nearest end. The ratio of tensions in string at P & Q is :

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EASY
A shell of mass, 20 g is fired by a gun of mass 100 kg. If the muzzle speed of the shell is 6 km min-1, what is the recoil speed of the gun?
HARD

A particle of mass 0.3 kg is subjected to a force F = Kx with K = 15 N/m, what will be its acceleration if it is released from a point x = 20 cm.

EASY
A small block of material having relative density 13 is immersed in a liquid and released. The block starts moving upwards with an acceleration a. The value of a is :(g is the acceleration due to gravity)
MEDIUM
A diwali rocket is ejecting 0.05kg of gases per second at a velocity of 400 m s-1. The accelerating force on the rocket is
EASY

Two similar trucks are moving with the same velocity on a road. One of them is loaded while the other is empty. Which of the two will require a larger force to stop it?

MEDIUM
A particle moving in the xy-plane experiences a velocity dependent force F=kυyi^+υxj^, where υx and υy are the x and y components of its velocity υ. If a is the acceleration of the particle, then which of the following statements is true for the particle ?
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A machine gun fires a bullet of mass 40 gram at a speed of 1200 m s-1. The man holding it can exert a maximum force of 144 N on the gun. How many bullets can he fire per second at the most?
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The pair with same dimension is ___.
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An object of mass 15 kg moves at a constant speed of 15 m s-1. A constant force, which acts for 5 s on the object, gives it a speed, 5 m s-1 in opposite direction. The force acting on the object is?
EASY
Consider a rocket is being fired. The kinetic energy of the rocket is increased by 16 times where as its total mass is reduced by half through the burning of fuel. The factor by which its momentum increases is
MEDIUM

A dynamometer D is attached to two masses m1=3 kg and m2=5 kg. Forces of f1=9 N and f2=25 N are applied to the masses as shown.

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The dynamometer will read :

MEDIUM
A particle having a mass 0.5 kg is projected under gravity with a speed of 98 m sec-1 at an angle of 60°.  The magnitude of the change in momentum (in N sec) of the particle after 10 seconds is g=9.8 m s-2