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A 400 kg jet dragster’s engine produces 5500 N of thrust. If the dragster starts from rest, how fast will it be moving after 1.5 s? After 3 s?

User Heeju
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Answer:

After 1.5 s speed = 20.625 m/s

After 3 s speed = 41.25 m/s

Step-by-step explanation:

1 Newton = 1 kg · m/s²

5500 N = 5500 kg · m/s² and this is the thrust (force) exerted on the jet

The impulse for 1.5 seconds is F x t

The change in momentum is m Δv where v is the change in velocity = v - u where v = final velocity and u = initial velocity

Since the dragster starts from res, u = 0 and Δv is simply v

Impulse = Momentum change

After 1.5 s for a thrust of 5500 N and a mass of 400 kg

5500 x 1.5 = 400 x v

v = 5500 x 1.5/400 = 20.625 m/s

After 3 seconds,
v = 5500 x 3/400 = 41.25 m/s

User Dmitri Soshnikov
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