An electron moves to the right with a speed of 0.90c rela- tive to the laboratory frame. a proton moves to the right with a speed of 0.70c relative to the electron. find the speed of the proton relative to the laboratory frame.

The speed of the proton relative to the laboratory frame is 0.981c

Explanation:

Given that,

Speed of electron v= 0.90c

Speed of proton u= 0.70c

We need to calculate the speed of the proton relative to the laboratory frame

Using formula of speed

Where, u = speed of the proton relative to the electron

v = speed of electron relative to the laboratory frame

Put the value into the formula

Hence, The speed of the proton relative to the laboratory frame is 0.981c

it is called kinetic energy