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A body of 5 kg is moving with a velocity of 20 m/s. If a force of 100 N is applied on it for 10 s in the same direction as its velocity, what will now be the velocity of the body

1) 200 m/s 2) 220 m/s 3) 240 m/s 4) 260 m/s Answer: 2) 220 m/s Solution: F=ma⇒100=5a⇒a=20m/s2 v=u+at=20+20×10=220m/s

A body A starts from rest with an acceleration a₁. After 2 seconds, another body B starts from rest with an acceleration a2. If they travel equal distances in the 5th second, after the start of A, then the ratio a₁: a₂ is equal to

1) 5 : 9 2) 5 : 7 3) 9 : 5 4) 9 : 7 Answer: 1) 5 : 9... View Article

Equation of displacement for any particle is s = 3t³ + 7t² + 14t + 8m. Its acceleration at time t =1sec is

1) 10 m/s2 2) 16 m/s2 3) 25 m/s2 4) 32 m/s2 Answer: 4) 32 m/s2 Solution: s = 3t3 + 7t2 +... View Article

The average velocity of a body moving with uniform acceleration travelling a distance of 3.06 m is 0.34 ms^–1. If the change in velocity of the body is 0.18 ms^–1 during this time, its uniform acceleration is

1) 0.01 m/s2 2) 0.02 m/s2 3) 0.03 m/s2 4) 0.04 m/s2 Answer: 2) 0.02 m/s2 Solution: Vaverage = Distance/time =... View Article

Acceleration of a particle changes when

1) Direction of velocity changes 2) Magnitude of velocity changes 3) Both of above 4) Speed changes Answer: 3) Both of... View Article

The distance travelled by a particle is proportional to the squares of time, then the particle travels with

1) Uniform acceleration 2) Uniform velocity 3) Increasing acceleration 4) Decreasing velocity Answer: 1) Uniform acceleration Solution: s = kt2 a... View Article

The motion of a particle is described by the equation x = a + bt², where a = 15 cm and b = 3 cm/s². Its instantaneous velocity at time 3 sec will be

1) 36 cm/sec 2) 18 cm/sec 3) 16 cm/sec 4) 32 cm/sec Answer: 2) 18 cm/sec Solution: x = a +... View Article

If a train travelling at 72 kmph is to be brought to rest in a distance of 200 metres, then its retardation should be

1) 20 ms–2 2) 10 ms–2 3) 2 ms–2 4) 1 ms–2 Answer: 4) 1 ms–2 Solution: Considering the equation v2... View Article

A truck and a car are moving with equal velocity. On applying the brakes both will stop after certain distance, then

1) Truck will cover less distance before rest 2) Car will cover less distance before rest 3) Both will cover... View Article

If a car at rest accelerates uniformly to a speed of 144 km/hr. in 20 s. Then it covers a distance of

1) 20 m 2) 400 m 3) 1440 m 4) 2880 m Answer: 2) 400 m Solution: Given, u = 0... View Article

The position x of a particle with respect to time t along x–axis is given by x = 9t²–t³, where x is in metres and t in second. What will be the position of this particle when it achieves maximum speed along the +xdirection

1) 32 m 2) 54 m 3) 81 m 4) 24 m Answer: 2) 54 m Solution: Given, x = 9t2–t3 v... View Article

A particle moves along a straight line such that its displacement at any time t is given by

S = t3– 6t2 + 3t + 4 metres The velocity when the acceleration is zero is 1) 3 ms–1... View Article

An elevator car, whose floor to ceiling distance is equal to 2.7 m, starts ascending with constant acceleration of 1.2 ms^–2, 2 sec after the start, a bolt begins falling from the ceiling of the car. The free fall time of the bolt is

1) √0.54 s 2) √6 s 3) 0.7 s 4) 1 s Answer: 3) 0.7 s Solution: Given, the distance between... View Article

A car moving with a speed of 40 km/hr. can be stopped by applying brakes after atleast 2 m. If the same car is moving with a speed of 80 km/hr., what is the minimum stopping distance

1) 8 m 2) 2 m 3) 4 m 4) 6 m Answer: 1) 8 m Solution: Considering the equation of... View Article

A car moving with a velocity of 10 m/s can be stopped by the application of constant force F in a distance of 20 m. If the velocity of the car is 30 m/s, it can be stopped by this force in

1) (20/3) 2) 20 m 3) 60 m 4) 180 m Answer: 4) 180 m Solution: Final velocity is zero and... View Article

The initial velocity of a body moving along a straight line is 7 m/s. It has a uniform acceleration of 4 m/s². The distance covered by the body in the 5th second of its motion is

1) 25 m 2) 35 m 3) 50 m 4) 85 m Answer: 1) 25 m Solution: The distance covered by... View Article

What determines the nature of the path followed by the particle

1) Speed 2) Velocity 3) Acceleration 4) Both (b) and (c) Answer: 4) Both (b) and (c) Solution: The nature of... View Article

A car start from rest and accelerates uniformly to a speed of 180 km h^–1 in 10 seconds. The distance covered by the car in this time interval is

1) 500 m 2) 250 m 3) 100 m 4) 200 m 5) 150 m Answer: 2) 250 m Solution: u=0,... View Article

A body moves for a total of nine seconds starting from rest with uniform acceleration and then with uniform retardation, which is twice the value of acceleration and then stops. The duration of uniform acceleration

1) 3 s 2) 4.5 s 3) 5 s 4) 6 s Answer: 4) 6 s Solution: Let a be the... View Article

The distance travelled by a particle starting from rest and moving with an acceleration 4/3 ms^–2, in the third second is

1) (10/3) m 2) (19/3) m 3) 6 m 4) 4 m Answer: 1) (10/3) m Solution: Distance travelled by the... View Article

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