A cyclist is travelling at 15 ms-1, she applies brakes so that she doesn't collide with the wall in front of her at a distance of 18 m. Calculate the magnitude of deceleration.
Correct answer: A. 6.3 ms-2
- A. 6.3 ms-2
- B. 5.3 ms-1
- C. 13 ms-1
- D. 12.5 ms-1
Explanation
Initial velocity, u=15m/sFinal velocity, v=0m/sDistance, s=18mAcceleration, a=?Using relation, v2 −u2 =2as02 −(15)2 =2a×18−225=36aa= 36 −225 =−6.25m/s2So, deceleration is 6.25m/s2 which is equal 6.3m/s2
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