A toy rocket with a mass of 300 g takes off in a vertical direction under the influence of gravity. It burns fuel at the rate of 25 g/s. The exhaust speed of the gases is 80 m/s. What is the speed of the rocket at the end of 10 seconds?
A)145 m/s
B)480 m/s
C)40 m/s
D)0 m/s
E)382 m/s

Question

Quizplus · Accepted Answer

The rocket equation (Tsiolkovsky's equation) is used to calculate the speed: v = v_exhaust * ln(m_initial/m_final) - g*t. Initial mass = 300 g, final mass = 300 g - 25 g/s * 10 s = 50 g. v = 80 m/s * ln(300/50) - 9.8 m/s² * 10 s = 145 m/s.

A Toy Rocket with a Mass of 300 G Takes