A bullet loses of its velocity passing through a plank. The least number of planks required to stop the bullet is (All planks offers same retardation)
1. 10
2. 11
3. 12
4. 23
A body starts from the origin and moves along the X-axis such that the velocity at any instant is given by , where t is in sec and velocity in m/s. What is the acceleration of the particle, when it is 2 m from the origin ?
1. 28 m/s2
2. 22 m/s2
3. 12 m/s2
4. 10 m/s2
The relation between time and distance is given by \(t=\alpha x^2+\beta x,\) where \(\alpha\) and \(\beta\) are constants. The retardation, as calculated based on this equation, will be (assume \(v\) to be velocity):
1. \(2\alpha v^3\)
2. \(2\beta v^3\)
3. \(2\alpha\beta v^3\)
4. \(2\beta^2 v^3\)
A point moves with uniform acceleration and v1, v2 and v3 denote the average velocities in the three successive intervals of time t1, t2 and t3. Which of the following relations is correct ?
1.
2.
3.
4.
The acceleration of a moving body can be found from:
1. Area under the velocity-time graph
2. Area under the distance-time graph
3. Slope of the velocity-time graph
4. Slope of the distance-time graph
The initial velocity of a particle is u (at t = 0) and the acceleration f is given by at. Which of the following relation is valid
1.
2.
3.
4. v = u
The initial velocity of the particle is 10 m/sec and its retardation is 2 m/sec2. The distance moved by the particle in 5th second of its motion is
1. 1 m
2. 19 m
3. 50 m
4. 75 m
A motor car moving with a uniform speed of 20 m/sec comes to stop on the application of brakes after travelling a distance of 10 m. Its acceleration is
1. 20 m/sec2
2. –20 m/sec2
3. –40 m/sec2
4. +2 m/sec2
The velocity of a body moving with a uniform acceleration of 2 m/sec2 is 10 m/sec. Its velocity after an interval of 4 sec is
1. 12 m/sec
2. 14 m/sec
3. 16 m/sec
4. 18 m/sec