Posted by **rahul patel** on Monday, November 21, 2011 at 8:47pm.

the kinetic energy of moving body ids directly praportional to its mass and the square of its speed.if the mass of a bullet is halved by what factor must its speed be increased to have the same kinetic energy as before?

- Math -
**Steve**, Tuesday, November 22, 2011 at 5:41am
E = k * m * v^2

If we halve the mass, now we have

E' = k * m/2 * v^2 = E/2

In order to get E' = E, we need a new velocity, v'

E' = k * m/2 * v'^2

and we see that

v'^2 must be 2v^2

so, v' = v√2

## Answer this Question

## Related Questions

- Algebra II - The kinetic energy of a moving body is directly proportional to ...
- Algebra II - The kinetic energy of a moving body is directly proportional to its...
- Algebra II - The kinetic energy of a moving body is directly proportional to its...
- physical science - Which of the following four bodies has the greatest kinetic...
- Physics - A 2.50g bullet, traveling at a speed of 425m/s, strikes the wooden ...
- physics - A bullet with mass m = 5.21 g is moving horizontally with a speed v=...
- Physics !!!!! HELP PLEASE - A hand gun fires a 12.0 g bullet at a speed of 400 m...
- physics - A 9.90-g bullet has a speed of 1.33 km/s. (a) What is its kinetic ...
- physics - A 9.90-g bullet has a speed of 1.33 km/s. (a) What is its kinetic ...
- Physics - A pitcher claims he can throw a 0.157 kg baseball with as much ...