Laws of motion practice · Mixed difficulty

In an elevator moving vertically up with an acceleration g, the force exerted on the floor by a passenger of mass M is

A mass of $4 \mathrm{~kg}$ rests on a horizontal plane. The plane is gradually inclined until at an angle $\theta=15^{\circ}$ with the horizontal, the mass just begins to slide. What is the coefficient of static friction between the block and the surface?

A machine gun fires a bullet of mas 65 g with a velocity of 1300 m/s. The man holding it can exert a maximum force of 169 N on the gun. The number of bullets he can fire per second will be

Choose the correct statement(s) from the following.
I. Recoiling of a gun is an application of principle of conservation of linear momentum.
II. Explosion of a bomb is based on second law of motion

A mass ${m}$ falls freely from rest. The linear momentum, after it has fallen through a height $h$, is :
( ${g}=$ acceleration due to gravity)

A $4 \mathrm{~kg}$ block is suspended from the ceiling of an elevator through a spring having a linear mass density of $19.2 \times 10^{-3} \mathrm{kgm}^{-3}$ Find the speed with respect to spring with which a wave pulse can proceed on the Spring if the elevator accelerates up at the rate of $2.0 \mathrm{~ms}^{-2}$ take $g=10 \mathrm{~ms}^{-2}$

Statement-I: When a ball of mass $m$ hits normally a wall with a velocity '$v$' and rebounds with same velocity $v$, impulse imparted to the wall is $2 m v$.
Statement-II: Impulse $=$ change in linear momentum

Select correct statement regarding friction

Impulse equals

A force of 40 newton acts on a body which is initially at rest. If the velocity of the body at the end of 10 seconds is $20\,\,\,{\text{m}}{{\text{s}}^{ - 1}},$ then mass of the body

If two masses (M & m) are connected on a horizontal plane and a force is applied on the combination, then the tension T depends on

The coefficient of friction between the tyres and the road is 0.25. The maximum speed with which a car can be driven round a curve a radius 40 m without skidding is is (assume $g = 10\;m{s^{ - 2}}$)

A cold soft drink is kept on the balance. When the cap is open, then the weight

A frictionless inclined plane of length l having inclination &theta; is placed inside a lift which is accelerating downward with an acceleration a($<g$) .&nbsp;If a block is allowed to move, down the inclined plane, from rest, then the time taken by the block to slide from top of the inclined plane to the bottom of the inclined plane is

No force is required for

An ice cart of mass 60 kg rests on a horizontal snow patch with coefficient of static friction $\frac{1}{3}$. Assuming that there is no vertical acceleration, find the magnitude of the maximum horizontal force required to move the ice cart $\left( {g = 9.8\;\mathrm{m}{\mathrm{s}^{ - 2}}} \right)$

A shell is fired with a muzzle velocity of $20\,m{s^{ - 1}}$ at an angle of ${60^0}$ with the horizontal. At the top of trajectory the shell explodes into 2 fragments of equal masses. One of them comes to rest. The distance at which second fragment touches the ground from gun will be…. $\left( {g = 10\,m/{s^2}} \right)$

A cubical block of mass $M$ vibrates horizontally with amplitude of $4 \mathrm{~cm}$ and a frequency of $2 \mathrm{~Hz}$. A small block of mass $m$ is placed on the bigger block. In order that the smaller block does not slide on the bigger block, the minimum value of the coefficient of static friction between the two blocks is

A person wants to drive on the vertical surface of a large cylindrical wooden 'well' commonly known as 'death well' in a circus. The radius of the well is $\mathrm{R}$ and the coefficient of friction between the tyres of the motorcycle and the wall of the well is $\mu_{\mathrm{s}}$. The minimum speed the motor cyclist must have in order to prevent slipping should be

A gun is mounted on a railroad car. The mass of the car, the gun, the shells and the operator is $50 \mathrm{~m}$ where $m$ is the mass of one shell. If the velocity of the shell with respect to the gun (in its state before firing) is $200 \mathrm{~m} / \mathrm{s},$ what is the recoil speed of the car after the second shot? Neglect friction.

Which of the following is a self adjusting force?

A bullet of mass 28 gm is fired from a rifle of mass 10 kg with a velocity of 100 m/s. The velocity of recoil of the rifle is

Physical independence of force is a consequence of

The x and y components of a force are 2 N and -3N. The force is

Assertion: A sphere cannot roll on a frictionless horizontal surface.
Reason: The tangential frictional force on the sphere exerts torque and causes it to roll.

A man squatting on the ground gets straight up and stand. The force of reaction of ground on the man during the process is

Identify the correct statement.

Assertion: The acceleration of a body down a rough inclined plane is greater than the acceleration due to gravity.
Reason: A body is able to slide on an inclined plane only when its acceleration is greater than the acceleration due to gravity.

An object is moving at constant velocity. The total force $F$ acting on the object is given by

Inertia of an object is directly dependent on