Question
A rocket with a lift-off mass 10,000 kg is blasted
upwards with an initial acceleration of 5.0 m s–2. Calculate the initial thrust (force) of the blast.Solution
Given that Mass of the rocket, m = 10,000 kg Initial acceleration, a = 5 m/s2 Acceleration due to gravity, g = 10 m/s2 Using Newton’s second law of motion, the net force (thrust) acting on the rocket is equal to F - mg = ma F = m(g + a) F = 10000 × (10 + 5) N = 10000 × 15 N = 15 × 104 N
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