Question

An object has a kinetic energy of 275 j and a momentum of magnitude 25.0 kg · m/s. find the (a) speed and (b) mass of the object.

Answer 1

Kinetic energy = momentum^2 / 2 x mass
Mass = (momentum^2/ Kinetic energy) / 2

Mass = (25^2 / 275) / 2
Mass = 1.136 kg.

momentum = mass x velocity

velocity = mass / momentum
velocity = 1.136 / 25
velocity = 0.04544 m/s

Answer 2

Answer: The correct answers are 482.4 m/s and 21.96 kg.

Step-by-step explanation:

The expression for the kinetic energy in terms of momentum of an object is as follows;

`KE=(p^(2) )/(2m)`

Here, KE is the kinetic energy, p is the momentum and m is the mass of the object.

It is given in the problem that an object has a kinetic energy of 275 j and a momentum of magnitude 25.0 kg · m/s.

Calculate the mass of the object.

`KE=(p^(2) )/(2m)`

Put p=25.0 kg · m/s and KE= 275 J.

`m=(25^(2) )/(2(275))`

`m=1.14 kg`

Calculate the speed of the object.

`KE=(1)/(2) mv^(2)`

Put m= 1.14 kg and KE= 275 J.

`v=\sqrt{(2(275))/(1.14) }`

v=21.96 m/s

Therefore, the speed of the object is 21.96 m/s and the mass of the object is 1.14 kg.