Question

A train starting from rest attains a velocity of 54 km per hour in 5 minutes assuming that the acceleration is uniform find the acceleration and the distance travelled by the train for attaining this velocity​

Answer 1

Explanation:

v=u+at

a=(v-u)/t -----------(1)

v=72 km/h

=20m/s

u=0

t=5*60 sec =300sec

by putting values of v,u,t in (1)

a=1/15 m/s2

s=ut +(1/2)at2

=0+(1/2)(1/15)(300)(300)

=3km

Answer 2

Answer:

Explanation:

Let S be the distance travelled by the train before attaining the final velocity V of 54km/hr, U be the initial velocity which was equal to zero (0), A be the uniform acceleration, T be the time.

Acc. to the question

V = 54km/h = 15m/s

T = 5min = 300s

We know,

V = U + AT

15 = A×300

0.05m/s² = A

Again,

S = UT + 1/2AT²

S = 1/2×0.05×90000 (since u = 0)

S = 2250m