Join TSR now and get all your revision questions answeredSign up now

Help with this question

    • Thread Starter
    Online

    1
    ReputationRep:
    A car was travelling at 30m/s. The driver applied the brakes to decelerate the car uniformly in 4.8 s.
    Calculate the braking distance?
    ???
    Have no clue
    It is involved with other sub questions like
    Calculate the deceleration which is, 6.25m/s^2
    And the braking force which is 5625N
    But how do you work out the braking distance
    In the answers, it says the answer is 73m BUT HOW DID THEY GET THAT?!?!
    Online

    3
    ReputationRep:
    (Original post by Sanjith Hegde123)
    A car was travelling at 30m/s. The driver applied the brakes to decelerate the car uniformly in 4.8 s.
    Calculate the braking distance?
    ???
    Have no clue
    It is involved with other sub questions like
    Calculate the deceleration which is, 6.25m/s^2
    And the braking force which is 5625N
    But how do you work out the braking distance
    In the answers, it says the answer is 73m BUT HOW DID THEY GET THAT?!?!
    This is a question involving constant acceleration.

    The acceleration can be calculated using "definition" of acceleration formula, where v = 0

    a = (v - u)/t

    The braking distance can found using either
    s = 1/2(u)t ---- this is area under the v-t graph
    or
    v2 = u2 + 2as

    The braking force can is using F = ma.
    Offline

    3
    ReputationRep:
    (Original post by Sanjith Hegde123)
    A car was travelling at 30m/s. The driver applied the brakes to decelerate the car uniformly in 4.8 s.
    Calculate the braking distance?
    ???
    Have no clue
    It is involved with other sub questions like
    Calculate the deceleration which is, 6.25m/s^2
    And the braking force which is 5625N
    But how do you work out the braking distance
    In the answers, it says the answer is 73m BUT HOW DID THEY GET THAT?!?!
    Do a=(v-u)/t to get the deceleration and then use s=ut+1/2at^2 to get the displacement.


    Posted from TSR Mobile
 
 
 
Poll
Which party will you be voting for in the General Election 2017?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.