Question

An empty rocket weighs 5000kg contains 40000kg fuel.if exhaust velocity of the fuel is 2km/sec,calculate the maximum velocity gained by the rocket

Answer 1

Answer:

it shouls be 2500 velocity

Answer 2

Answer:

Maximum velocity gained by the rocket is 18.209 km/s

Explanation:

The weight of empty rocket is=5000kg,

Amount of fuel it contains is= 40000kg.

Exhaust velocity of the fuel is =2 km/sec = 2000m/s

The maximum velocity gained by the rocket is given by $v_{max}=v_r\ln (\frac{m_0}{m} )$, where $v_r$ is the exhaust velocity and $m_0$ and m is mass of rocket + fuel and rocket respectively.

hence putting values in the formula we get, $v_{max}=2000*\ln (\frac{45000}{5000} )=18209.95 m/s$

Maximum velocity gained by the rocket is 18.209 km/s