A body is obliquely projected from the horizontal ground. The magnitude of gravity's power delivered during its motion from the ground to the topmost point is:
| 1. | Constant
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| 2. | Increases continuously
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| 3. | Decreases continuously
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| 4. | May increase or decrease depending on the angle of projection |

1. \(50~\text{J}\)
2. \(100~\text{J}\)
3. \(25~\text{J}\)
4. Zero
A particle is suspended by a light rod of length l. The minimum speed at which the particle should be projected, so that it moves in a vertical circle, is:
| 1. | \(3 \sqrt{g l} \) | 2. | \(\sqrt{2 g l} \) |
| 3. | \(2 \sqrt{g l} \) | 4. | \(\sqrt{5 g l}\) |
According to the work-energy theorem, the change in kinetic energy of a body is equal to work done by:
1. Non-conservative force on the particle
2. Conservative force on the particle
3. External force on the particle
4. All the forces on the particle
A block is carried slowly up an inclined plane. If \(W_f\) is work done by the friction, \(W_N\) is work done by the reaction force, \(W_g\) is work done by the gravitational force, and \(W_{ex}\) is the work done by an external force, then choose the correct relation(s):
1. \(W _N + W _f + W _g + W _{ex} = 0\)
2. \(W _N = 0\)
3. \( W _f + W _{ex} = - W _g\)
4. All of these
The position of a particle \((x)\) varies with time \((t)\) as \(x = (t - 2)^2\), where \(x\) is in meters and \(t\) is in seconds. Calculate the work done during \(t=0\) to \(t=4\) s if the mass of the particle is \(100~\text{g}.\)
1. \(0.4~\text{J}\)
2. \(0.2~\text{J}\)
3. \(0.8~\text{J}\)
4. zero
A particle of mass m is moving in a circular path with a speed v = kt, where k is constant and t is time. The instantaneous power delivered to the particle is:
| 1. | Zero | 2. | mkt |
| 3. | 4. |
A position-dependent force; \(F=6+8x-3x^2\) N acts on a small body of mass \(3\) kg, displacing it from \(x=0\) to \(x=2\) m. The work done in joule is:
1. \(20\)
2. \(40\)
3. \(10\)
4. \(12\)
A car of mass 100 kg and traveling at 20 m/s collides with a truck weighing 1 tonne traveling at 9 km/h in the same direction. The car bounces back at a speed of 5 m/s. The speed of the truck after the impact will be:
1. 11.5 m/s
2. 5 m/s
3. 18 m/s
4. 12 m/s
Which of the following remains unchanged (for the system) during an inelastic collision?
| 1. | Mechanical energy | 2. | Kinetic energy |
| 3. | Momentum | 4. | All of the above. |