Question

Kinetic energy varies jointly as the mass and the square of the velocity. A mass of 1515 grams and velocity of 77 centimeters per second has a kinetic energy of 147147 ergs. Find the kinetic energy for a mass of 1010 grams and velocity of 99 centimeters per second?

Answer 1

The second kinetic energy is 162 J.

Step-by-step explanation:

Given that,

Mass,
`m_1=15\ g`

Velocity,
`v_1=7\ cm/s`

Kinetic energy,
`K_1=147\ ergs`

Mass,
`m_2=10\ g`

Velocity,
`v_2=9\ cm/s`

We need to find kinetic energy
`K_2`. Kinetic energy is given by :

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

So,

`(K_1)/(K_2)=(m_1)/(m_2)* (v_1^2)/(v_2^2)\\\\K_2=(K_1)/((m_1)/(m_2)* (v_1^2)/(v_2^2))\\\\K_2=(147)/((15)/(10)* (7^2)/(9^2))\\\\K_2=162\ J`

So, the second kinetic energy is 162 J.