Question

A body moving along a straight line at 20m/s undergoes an acceleration of -4m/s² calculate
a- The speed of the body after 2 sec
b- Distance covered by the body to stop.

Answer 1

Answer:

28m/s

Explanation:

u= 20 m/s

a=4m/s^2

v= u+at = 20+4×2=28 m/s

Answer 2

Answer:

a. v = u+at =20+(-4)2 = 20-8 = 12m/s

b. (V-u)/a = t = 0-20/-4 = 5sec

then S = ut +1/2×at^2 = 20×5+1/2×-4×5^2 = 100+(-50) = 50m answer.

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