A truck of mass \(30,000~\text{kg}\) moves up an inclined plane of slope \(1\) in \(100\) \(\left(\tan\theta = \frac{1}{100}\right)\) at a speed of \(30~\text{km/h}\). The power of the truck is: (given \(g=10~\text{ms}^{-2}\)):
1. | \(25~\text{kW}\) | 2. | \(10~\text{kW}\) |
3. | \(5~\text{kW}\) | 4. | \(2.5~\text{kW}\) |
A pump ejects 12,000 kg of water at a speed of 4 m/s in 40 s. The average rate at which the pump is working is:
1. 0.24 kW
2. 2.4 W
3. 2.4 kW
4. 24 W
A spring 40 mm long is stretched by the application of force. If 10 N force is required to stretch the spring through 1 mm, then work done to stretch the spring 40 mm is equal to:
1. | 84 J | 2. | 68 J |
3. | 23 J | 4. | 8 J |
A block of mass 2 kg moving with a velocity of 10 m/s on a smooth surface hits a spring of force constant N/m as shown. The maximum compression in the spring will be:
1. | 5 cm | 2. | 10 cm |
3. | 15 cm | 4. | 20 cm |
A body is displaced from (0, 0) to (1m, 1m) along the path x=y by a force . The work done by this force will be :
1.
2.
3.
4.
A block of mass m initially at rest, is dropped from a height h onto a spring of force constant k. If the maximum compression in the spring is x, then:
1.
2.
3.
4.
A block of mass \(\text M\) moving on the frictionless horizontal surface collides with the spring of spring constant \(\text K\)and compresses it by length \(\text L\). The maximum momentum of the block after the collision will be:
1. | Zero | 2. | \(ML^2 \over K\) |
3. | \(\sqrt{MK}~L\) | 4. | \(KL^2 \over 2M\) |
A body of mass m accelerates uniformly from rest to v1 in time t1. As a function of time t, the instantaneous power delivered to the body will be:
1.
2.
3.
4.
A body of mass 1 kg is thrown upwards with a velocity of It momentarily comes to rest after attaining a height of 18 m. How much energy is lost due to air friction?
1. 20 J
2. 30 J
3. 40 J
4. 10 J
1. | no work is done by the tangential force. |
2. | no work is done by the centripetal force. |
3. | work done by the tangential force is always positive. |
4. | work done by the centripetal force is negative. |