A machine gun fires 240 bullets per minute with certain velocity. If the mass of each bullet is `10^(-2)` kg and the power of the gun is 7.2 kW, find the velocity with which each bullet is fired.

Explanation

Mass of each bullet `m = 10^(-2)` kg
power = 7.2 kW = `7.2 xx 10^(3)` W
`(n)/(t)=240"bullets"//min=(240)/(60)"bullets"//sec.`
power = `(n((1)/(2)mv^(2)))/(t)=7.2xx10^(3)=(240xx(1)/(2)xx10^(-2)xxv^(2))/(60)`
`v^(2)=(7.2xx10^(3)xx2)/(4xx10^(-2))=(7.2)/(2)xx10^(5)=3.6xx10^(5)`
v = 600 m/s