A car is moving with velocity v. It stops after applying breaks at a distance of 20 m. If the velocity of the car is doubled, then how much distance it will cover (travel) after applying breaks?
1. 40 m
2. 80 m
3. 160 m
4. 320 m
A body starts falling from height 'h' and if it travels a distance of h/2 during the last second of motion, then the time of flight is (in seconds):
1.
2.
3.
4.
For a particle, displacement time relation is given by . Its displacement, when its velocity is zero will be:
1. \(2\) m
2. \(4\) m
3. \(0\)
4. none of the above
A particle starts from rest with constant acceleration. The ratio of space-average velocity to the time-average velocity is:
where time-average velocity and space-average velocity, respectively, are defined as follows:
1.
2.
3.
4.
The motion of a particle is given by the equation The value of the acceleration of the particle at t = 1 s is :
1. | 10 m/s2 | 2. | 32 m/s2 |
3. | 23 m/s2 | 4. | 16 m/s2 |
A particle is thrown vertically upward. Its velocity at half its height is \(10\) m/s. Then the maximum height attained by it is: (Assume, \(g=\) \(10\) m/s2)
1. \(8\) m
2. \(20\) m
3. \(10\) m
4. \(16\) m
If a ball is thrown vertically upwards with speed u, the distance covered during the last ‘t’ seconds of its ascent is:
1. ut
2.
3.
4.
A man throws some balls with the same speed vertically upwards one after the other at an interval of 2 seconds. What should be the speed of the throw so that more than two balls are in the sky at any time? (Given g = 9.8 m/s2)
1. More than 19.6 m/s
2. At least 9.8 m/s
3. Any speed less than 19.6 m/s
4. Only with a speed of 19.6 m/s
A ball of mass 2 kg and another of mass 4 kg are dropped together from a 60 feet tall building. After a fall of 30 feet each towards the earth, their respective kinetic energies will be in the ratio of:
1. 1: 4
2. 1: 2
3. 1:
4. :1
The displacement \(x\) of a particle varies with time \(t\) as \(x = ae^{-\alpha t}+ be^{\beta t}\)
, where \(a,\) \(b,\) \(\alpha,\) and \(\beta\) are positive constants. The velocity of the particle will:
1. | \(\alpha\) and \(\beta.\) | be independent of
2. | go on increasing with time. |
3. | \(\alpha=\beta.\) | drop to zero when
4. | go on decreasing with time. |