Home
Class 11
PHYSICS
In a ballistics demonstration a police o...

In a ballistics demonstration a police officer fires a bullet of mass `50.0 g` with speed `200 ms^(-1)` (see Table 6.2) on soft plywood of thickness 2.00 cm. The kinetic energy. What is the emergent speed of the bullet?

Text Solution

Verified by Experts

The initial kinetic energy of the bullet is `mv^(2)"/"2= 1000 J`. It has final kinetic energy of `0.1xx1000= 100 J`. If `v_(f)` is the emergent speed of the bullet,
`(1)/(2) mv_(f)^(2)= 100 J`
`v_(f)= sqrt((2xx100 J)/(0.05 kg))`
`= 63.2 ms^(-1)`.
The speed is reduced by approximately 68% (not 90%).
Promotional Banner

Similar Questions

Explore conceptually related problems

Calculate de-Broglie wavelength associated with a rifle bullet of mass 2 gram moving with a speed of 400 ms^(-1) .

A bullet of mass 0.04 kg moving with a speed of 90 m s^(-1) enters a heavy wooden block and is stopped after a distance of 60 cm. What is the average resistive force exerted by the block on the bullet?

A machine gun fires 25 bullets of mass 0.1 kg each, per minute. If the speed of the bullet is 200 ms^(-1) , then calculate the power developed by the gun.

A block of mass 0.50 kg is moving with speed of 2.00 ms^(-1) on a smooth surface. It strikes another mass of 1.00 kg and then they move together as a single body. The energy loss during the collisions is

What is the de Broglie wavelength of (a) a bullet of mass 0.040 kg travelling at the speed of 1.0 km//s , (b) a ball of mass 0.060 kg moving at a speed of 1.0 m//s, and (c) a dust particle of mass 1.0 xx 10^(-9) kg drifting with a speed of 2.2 m//s ?

A bullet travelling at 200ms^(-1) penetrates a wooden block of thickness 0.20 m and comes out at 20ms^(-1) . Calculate the retardation produced inside the block. What additional thickness is required to stop the bullet.

In a chamber, a uniform magnetic field of 8.0 G is maintained. An electron with speed of 4.0 times 10^(6)ms^(-1) enters the chamber in a direction normal to the field. (a) Describe the path of the electron. (b) What is the frequency of revolution of the electron? (c) What happens to the path of electron if it progessively loses its energy due to collisions with the atoms or molecules of the environment?