Newton's Laws of Motion Questions
A steel rod of length 25 cm has a cross-sectional area of 0.8 cm². The force required to stretch this rod by the same amount as the expansion produced by heating it through 100°C (α = 10⁻⁵ °C⁻¹, Young's modulus of steel = 2 × 10¹¹ N/m²) is:
The respective displacements (in cm) of two particles of a medium disturbed by a wave propagating at the rate of 2 ms⁻¹ are given by y₁ = 2 sin(ωt − x/8) and y₂ = 2 sin(ωt − π/8). The speed of the wave is:
A system is shown in the figure. The time period for SHM of the two blocks will be:
A gas mixture consists of 2 moles of oxygen and 4 moles of argon at temperature T. Neglecting all vibrational modes, the total internal energy of the system is:
Following figure shows two processes A and B for a gas. If ΔQₐ and ΔQᵦ are the amount of heat absorbed by the system in two cases, and ΔUₐ and ΔUᵦ are changes in internal energies, respectively then :
A bimetallic strip consists of metals X and Y. It is mounted rigidly at the base as shown in the figure. The metal X has a higher coefficient of expansion as compared to that for metal Y. When the bimetallic strip is placed in a cold bath ?
A planet has twice the density of earth but the acceleration due to gravity on its surface is exactly the same as on the surface of earth. Its radius in terms of earth R will be
Figure shows three forces applied to trunk that moves leftward by 3m over a smooth floor. The force magnitudes are F1 = 5N, F2 = 9N and F3 = 3N . The net work done on the trunk by the three forces
A body moves along a horizontal circular path of radius 5 m. The coefficient of friction between the surface of the path and the body is 0.5 . The maximum angular velocity (in rad/sec) with which the body should move so that it does not leave the pat
A block slides down a frictionless incline making an angle θ with the floor at an elevator. The elevator is descending with an acceleration a. The value of normal reaction acting on the block is
The maximum velocity (in ms⁻¹) with which a car driver can traverse a flat curve of radius 150 m and coefficient of friction 0.6 to avoid skidding is :
Two blocks of masses 2m and m are in equilibrium as shown in the figure. Now the string between the blocks is suddenly broken. The acceleration of the blocks A and B respectively at that instant are :
A particle of mass m falls from rest through a resistive medium having resistive force, F = −kv, where v is the velocity of the particle and k is a constant. Which of the following graphs represents velocity (v) versus time (t) ?
Block B of mass 100 kg rests on a rough surface of friction coefficient μ = 1/3. A rope is tied to block B as shown in figure. The maximum acceleration with which boy A of mass 25 kg can climb on rope without making block to move is
A block of mass 2 kg is pushed on a rough horizontal surface with momentum 4√10 kg m/s. If block stopped after moving a distance 8 m on the surface, then coefficient of friction between the block and the surface is
Find out the velocity of block B in a pulley block system as shown in figure.
A car turns a corner on a slippery road at a constant speed of 12 m/s. If the coefficient of friction is 0.4, the minimum radius of the arc in metre in which the car turns is
In the given arrangement, all surfaces are smooth and strings are ideal. What acceleration should be given to the block M so that the block m₂ does not slide down?
Two particles of masses m and 4m are moving in horizontal circles. The heavier mass moves in a circle of radius , while the lighter mass moves in a circle of radius R. If both particles experience the exact same centripetal force, the speed of the li
The acceleration-time graph of a particle moving in straight line is shown. If initial velocity of the particle is 6 m/s, then velocity at the end of 4 second will be
A block of mass 0.1 kg is pressed against a wall with a horizontal force of 5 N as shown in the figure. If the coefficient of friction between the wall and the block is 0.5, then the frictional force acting on the block will be (g = 9.8 m/s²):
A wagon weighing 1000 kg is moving with a speed 50 km/hr on smooth horizontal rails, A mass of 250 kg is dropped into it. The speed with which it moves now is:
Three equal weights each of mass 3 kg are hanging on a strings passing over a fixed ideal pulley as shown in figure. What is the tension T in the string connecting weights B and C? (g = 10 m/s²)
n bullets normally strike on a wall per second with speed v and rebound with the same speed. What will be the force exerted on the wall by bullets if mass of each bullet is m?
A car moving on a horizontal road may be thrown out of the road while taking a sharp turn:
A block of mass 5 kg is suspended by a massless spring on a smooth inclined plane as shown in figure. The extension in the spring when block is in equilibrium is: (Given spring constant K = 100 N/m, g = 10 m/s²)
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R: Assertion A: Mutual interaction of force between two bodies follows Newton’s third law. Reason R: Single isolated force without reaction can be poss
A rocket of mass 800 kg is to be projected vertically upwards. The gases are exhausted vertically downwards with velocity 40 m/s with respect to the rocket. What is the minimum rate of burning fuel, so as to just lift the rocket upwards against the g
In figure, a ball of mass m₁ and a block of mass m₂ are joined together with an inextensible string as shown in the figure. The ball can slide on a smooth horizontal surface. If v₁ and v₂ are the respective speeds of the ball and the block, then the
For a body of 50 kg mass moving in a straight line, the velocity-time graph is shown in figure. The net force acting on the body is:
A particle is in a straight-line motion with uniform velocity. A force is not required:
Choose the correct option regarding inertia of object.
Thin uniform rope of mass m is hanging from rough horizontal table as shown in figure. If its hanging length becomes 2/5th of its entire length then it is on the verge of slipping. Magnitude of friction force on the rope when it just about to slip is
For a particle moving with speed v in a circle of radius r in uniform circular motion inside a smooth cone, the angle θ with the vertical is given by: (g is acceleration due to gravity)
The only force (F) acting horizontally on an object of mass 10 kg varies with time (t) as shown. If the object starts from rest, what is the speed at t = 5 s?
Two blocks of masses ma and mb are connected with ideal string and ideal pulley as shown in the figure then ratio of Ta and Tc is:
A conical pendulum makes an angle 45° with vertical. If the length of string is 10√2 m. The time period of pendulum is: (Take g = 10 m/s²)
In a ‘well of death’ a rider drives round the inner wall of a hollow cylindrical chamber of diameter 20 m. If the coefficient of friction between tyres and inner wall of a hollow cylinder is 0.5, then the minimum speed of the rider without sliding do
A ball is suspended by a thread from the ceiling of a car. The brakes are applied and the speed of the car changes from 36 km h⁻¹ to zero uniformly in 5 seconds. The angle by which ball deviates from the vertical is (g = 10 ms⁻²);
Two blocks A and B having masses 5 kg and 10 kg respectively are placed one over other on a smooth horizontal surface as shown in the diagram. The coefficient of friction between the blocks is 0.2. The maximum force that should be applied on upper bl
Figure shows a light spring balance connected to two blocks of mass 20 kg by a light string passing over frictionless pulley. What will be the reading of the spring balance?
Consider the situation shown in the diagram given below. The net force on the pulley due to tension T in the string will be;
A sports car is rounding a flat unbanked curve with radius of 230 m. The coefficient of friction between road and tyre is 0.96, the maximum speed at which driver can take the turn without sliding is nearly; (g = 10 m/s²)
For a variable mass system, the correct form of Newton’s second law will be;
A bomb of mass 4 kg initially at rest, explodes and breaks into three fragments of masses in the ratio 1 : 1 : 2. The two pieces of equal mass fly off perpendicular to each other with a speed 10 m/s each. The speed of heavier fragment is:
A gramophone record is revolving with an angular velocity ω. A coin is placed at a distance r from the centre of the record. The static coefficient of friction is 0.5. The coin will revolve with the record without slipping if: (g is acceleration due
In the given figure, what will be the magnitude of acceleration of block of mass 6 kg? (g = 10 m/s²)
A ball of mass 0.5 kg is dropped from a height of 20 m, it strikes the ground and rebound to the same height. The magnitude of impulse imparted by the ground to the ball is: (g = 10 m/s²)
A cubical block rests on a horizontal plane having coefficient of friction μ = √3. The angle through which the plane be inclined to the horizontal so that the block just begins to slide down will be:
A uniform rope of mass M and length L is fixed at its upper end vertically from a rigid support. Then the tension in the rope at the distance L/4 from the rigid support is: