a motor car moving with a velocity of 54km/hr is brought to rest in 5sec and 30 meter find the retardation in each case
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a motor car moving with a velocity of 54km/hr is brought to rest in 5sec and 30 meter find the retardation in each case
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Given:
A motor car moving with a velocity of 54km/hr is brought to rest in 5sec and 30 meter.
To find:
Retardation of car in each case ?
Calculation:
First , let's convert unit of velocity from km/hr to m/s : simply multiply km/hr value with 5/18.
1st case:
[tex]v = u + at[/tex]
[tex] \implies \: 0 = 15 + a(5)[/tex]
[tex] \implies \: 5a= - 15 [/tex]
[tex] \implies \:a= - 3 \: m/ {s}^{2} [/tex]
So, acceleration is -3 m/s².
2nd case:
[tex] {v}^{2} = {u}^{2} + 2as[/tex]
[tex] \implies \: {0}^{2} = {(15)}^{2} + 2a(30)[/tex]
[tex] \implies \: 60a = - 225[/tex]
[tex] \implies \: a = - 3.75 \: m/ {s}^{2} [/tex]
So, acceleration is 3.75 m/s².