CfE Higher Physics Multiple Choice

Hi, I'm unsure at how the answer is B for this question. I got the answer to be C for it! Can someone explain why the answer is B? Thank you!

A spacecraft is travelling in a straight line with a speed of 1·4 × 103 ms–1. Booster rockets are fired for 50 s and the speed increases to 1·5 × 103 ms–1. (the threes are to the power i.e. 1.4x10 to the power of 3, and 1.5x10 to the power of 3)

What is the average acceleration of the space craft?

A 2·0 × 10–3 ms–2
B 0·20 ms–2
C 2·0 ms–2
D 5·0 ms–2
E 500 ms–2

(edited 8 years ago)

Reply 1

1420787

I get C too, 100/50?