A few days ago
Anonymous

Uniform Deceleration?

I dont know how to solve this question. An answer and a explanation would be appreciated. Thanks.

A jet landing at 300km/hr needs to stop before the end of a 1000m runway. What is the minimum uniform deceleration required?

a. 3.5 m/s2 b. 45 m/s2 c. 7.7m/s2

d. 83m/s2

Top 2 Answers
A few days ago
Anonymous

Favorite Answer

Initial jet speed = 300

Final velocity = 0

Let the de-accelaration be ‘-a’ (because it is negative acceleration)

use v^2-u^2 = -2aS

300 km/hr = 300*1000/3600 = 1000/12 = 250/3 m/s

0^2 – (250/3)^2 = -2* a*1000

a = 3.47 m/sec^2 … ANSWER shud be (a) since it is closest

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5 years ago
Anonymous
Since the answers are in m/s change the speed of the jet to m/s. v^2= 300km/hr= 83.3 m/s v^2=2as and solve for acceleration (deceleration) a=v^2/(2s) =(83.3)^2/2(1000) =3.46 m/s^2 Answer is a) 3.5 m/s^2
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