Question

a machine gun fires 360 words per minute and each bullet travels with a velocity 600 metres per second is the mass of each Bullet is 5 grams find power of machine gun

Answer 1

number of bullets per second = 360/60 = 6
velocity = 600 m/s
mass = 5g = 0.005 kg

energy required for firing 1 bullet = 1/2 × 0.005 × 600^2 = 900J

For 6 bullets per sec, power = 900×6 J/s = 5400 W

Answer 2

Machine gun fires 360 bullets in 1 minute
Number of bullets (n) it will fire in 1 second is 360/60 = 6

Kinetic energy of “n” bullets = 0.5 nmv²
= 0.5 × 6 × 5 × 10⁻³ kg × (600 m/s)²
= 5400 J
= 5.4 kJ

Power of machine gun = Kinetic energy of “n” bullets / Time
= 5.4 kJ / 1 s
= 5.4 kW