Question

a cyclist is travelling at 15 m¹.she applies brakes so that she does not collide with the wall 18m away what deceleration must she have​

Answer 1

QUESTION:

A cyclist is travelling at 15 m¹.she applies brakes so that she does not collide with the wall 18m away what deceleration must she have

ANSWER:

Retardation produced by the brakes to stop the bicycle = -6.25 m/s²

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Explanation:

given that,

a cyclist is travelling at 15 m/s

so,

here

initial velocity of the girl = 15 m/s

and also given that

there is a wall in front of her

distance from her to wall = 18 m

she applies brakes so that she does not collide with the wall

so,

here final velocity of her = 0 [stops]

now to find,

deceleration must she have.

here we have ,

initial velocity (u) = 15 m/s

final velocity (v) = 0

distance (s) = 18 m

by the equation of motion

v² = u² + 2as

where,

a = acceleration

now,

putting the values,

(0)² = (15)² + 2a(18)

36a + 225 = 0

36a = -225

a = -225/36

a = -6.25 m/s²

negation of acceleration shows the Retardation.

so,

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Retardation produced by the brakes to stop the bicycle = -6.25 m/s²

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Answer 2

Answer:

the answer will be -6.25m/s^2

Explanation: