A 5000 kg rocket is set for vertical firing. The exhaust speed is 800 m/s. To give an initial upward acceleration of 20 ms–2 the amount of gas ejected per second to supply the needed thrust will

Q: A 5000 kg rocket is set for vertical firing. The exhaust speed is 800 m/s. To give an initial upward acceleration of 20 ms–2 the amount of gas ejected per second to supply the needed thrust will (g = 10 ms–2)

(a) 127.5 kg/s

(b) 187.5 kg/s

(c) 185.5 kg/s

(d) 137.5 kg/s

Ans: (b)