Question

A vehicle travelling at90 km/h slows down to 36 km/h in 7s .find the retardation

Answer 1

Answer:

retardation = rate of change of velocity

a=(v-u) /t

=(90-36) /7

= 54/7

retardation=-54/7

Answer 2

${\large{\bf{\red{\clubs{\underline{Given :}}}}}}$

A vehicle travelling at90 km/h slows down to 36 km/h in 7s .

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${\large{\bf{\blue{\clubs{\underline{To Find:}}}}}}$

Find the retardation of the vehicle.

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${\large{\bf{\orange{\clubs{\underline{Solution :}}}}}}$

Formula for retardation :

${\blue{\bigstar{\pink{\boxed{\mathfrak{Retardation = \frac{change \: in \: velocity}{tim \: taken} }}}}}}$

Here,

${\sf{\purple{v = 90km/h}}}$

${\sf{\purple{u = 36km/h}}}$

${\sf{\purple{Time = 7s}}}$

${\sf{\purple{Retardation = ?}}}$

First,

Converting values

${\sf{\purple{90km/h = 25m/s}}}$

${\sf{\purple{36km/h = 10m/s}}}$

Now,

${\bf{\green{\mapsto{= \frac{v - u}{time} }}}}$

${\bf{\green{\mapsto{ \frac{25 - 10}{7} }}}}$

${\bf{\green{\mapsto{ {\cancel\frac{15}{7} }}}}}$

${\blue{\underbrace{\red{\boxed{\mapsto{\bf{2.142m/s.}}}}}}}$

So,

The retardation of car is 2.142m/s.

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${\sf{\pink{\blue{\fcolorbox{green}{red}{\underline{XitzNobitaxX}}}}}}$