Question

From an automatic gun a man fires 360 bullets per minute with a speed of 360 km/hour. If each weighs 20 g, the power of the gun is :

• A. 600 W
• B. 300 W
• C. 150 W
• D. 75 W

Answer 1

Answer: (A)

Here : Number of bullets n = 360, Time = 1 minute =60 sec, Mass of bullet = $\frac{T_1}{T_2}=\frac{x-mg}{x+mg}\left(\because Given\frac{T_1}{T_2}=\frac{3}{5}\right)$ Velocity v = 360 km/hr $\frac{3}{5}=\frac{x-mg}{x+mg}$ Now power of gun is given by $3x+3mg=5x-5mg$ $x=4mg$ = 600 watt