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oksano4ka [1.4K]

2 years ago

12

A 900 kg car is traveling at 20 m/s along the road. What force must be applied to the car to stop it in a distance of 30 m2 Assu

me a
constant change in velocity.
A. 6000 N
B. 12,000 N
C. 7000 N
D. 18,000 N
h

1 answer:

serg [7]2 years ago

5 0

Answer:

A. 6000 N

Explanation:

v²=u²+2as

0²=20²+2x30xa

-400=60a

a=-400/60

a =-6.667m/s²

f =ma

f = 900 x 6.667 = 6003N

F = 6000N

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