Physics
A bullet of mass 50g is moving with a velocity of 500ms-1. It penetrates 10 cm into a still target and comes to rest.
Calculate:
(a) the kinetic energy possessed by the bullet, and
(b) the average retarding force offered by the target.
Related Questions
How much work is needed to be done on a ball of mass 50g to give it a momentum of 5 kg m s-1?
How much energy is gained by a box of mass 20 kg when a man
(a) carrying the box waits for 5 minutes for a bus?
(b) runs carrying the box with a speed of 3 ms-1 to catch the bus?
(c) raises the box by 0.5 m in order to place it inside the bus?
(g=10 ms-2)
A spring is kept compressed by a small trolley of mass 0.5 kg lying on a smooth horizontal surface as shown. When the trolley is released, it is found to move at a speed of v = 2 ms-1. What potential energy did the spring possess when compressed?
According to the principle of conservation of mechanical energy :
- Potential energy of a system is always greater than its kinetic energy
- Kinetic energy of a system is always greater than its potential energy
- Mechanical energy is always converted into heat energy
- Total mechanical energy of a system remains constant if no external force is worked on it.