A train is travelling at a speed of 90, km h ^{-1} . Breaks are applied so as to produce a uniform a

English

Gujarati

Hindi

7. MOTION

normal

A train is travelling at a speed of $90\, km h ^{-1}$. Breaks are applied so as to produce a uniform acceleration of $0.5\, m s ^{-2}$. Find how far the train will go before it is brought to rest.

Option A

Option B

Option C

Option D

Solution

Given $u=90 km h ^{-1}=5 \times \frac{90}{18}=25 m s ^{-1}, v=0$

$a=-0.5 m s ^{-1}, S =?$

Using

$v^{2}-u^{2}=2 a S$

$0-(25)^{2}=2 \times-0.5 \times 5$

or $S =625 m$

Standard 9

Science

Share

Similar Questions

An aeroplane lands at $216\, km\, h ^{-1}$ and stops after covering a runway of $2\, km .$ Calculate the acceleration and the time, in which its comes to rest.

medium

Write true or false for the following statements

Motion along a curved line is called translatory or rectilinear motion.

easy

If the displacement of a body is proportional to the time elapsed, what type of motion does the body possess ?

easy

A car starts from rest and moves along the $x-$ axis with constant acceleration $5\, ms^{-2}$ for $8\,\sec $. If it then continues with constant velocity, what distance will the car cover in $12\,\sec $ since it started from the rest ?

medium

$(a)$ Derive graphically the equation for velocity$-$time relation.

$(b)$ Name the device used to measure distance travelled by a vehicle.

$(c)$ Can displacement of a moving object be zero ? Give reason.

medium