Question

A train starting from rest attains a velocity of 72 km per hour in 5 minute as human the acceleration is uniform find .
1) the acceleration
2) the distance travelled by the train for attaining this velocity ​

Answer 1

Hint: Use the fact whenever a body starts moving from rest, the final velocity attained by that object is a multiplication of the uniform acceleration and time taken to achieve that final velocity. Use laws of motion to calculate the distance travelled.

Complete step-by-step answer: 

Given,

Initial velocity

=u=0m/s=u=0m/s

 

Final velocity=V=72km/h=V=72km/h 

Time=5min=5min 

We will convert minutes into hours. 

=560h=112h=560h=112h 

We have to find out acceleration:

We will denote acceleration by a and distance travelled by s.

Formula used:

a=v−ut⇒a=72−0112⇒a=72×12=864km/h2a=v−ut⇒a=72−0112⇒a=72×12=864km/h2 

Hence the acceleration is 864km/h2864km/h2.

or

Now, the distance travelled by train:

Formula used: 

s=ut+12at2=0×112+12(864)(112)

We have to find out acceleration: We will denote acceleration by a and distance travelled by s. Hence the acceleration is 864km/h2. Hence, the distance travelled by train is 3km.