Question

A train starts to move from rest. After 5 minutes, its velocity becomes 90km/hr. What is its acceleration

Answer 1

Answer:

• 0.084m/s² is the required acceleration.

Explanation:

Given:-

• Initial velocity ,u = 0m/s
• Final velocity ,v = 90km/h
• Time taken ,t = 5min

To Find:-

• Acceleration,a

Solution:-

According to the Question also

It is given that train starts to move from rest. After 5 minutes, its velocity becomes 90km/hr.

we have to calculate the acceleration of the train .

Firstly we change the unit here.

→ Final velocity = 90×5/18

→ Final velocity = 5×5

→ Final velocity = 25m/s .

______________________

→ Time taken = 5×60s

→ Time taken = 300s

Now calculating the acceleration of the train. As we know that acceleration is defined as the rate of change in velocity.

• a = v-u/t

where,

v is the final velocity

a is the acceleration

u is the initial velocity

t is the time taken

Substitute the value we get

→ a = 25-0/300

→ a = 25/300

→ a = 0.084m/s²

• Hence, the acceleration of the train is 0.084m/s².

Answer 2

Answer:-

• initial velocity=u=0m/s
• Final velocity=v=90km/h

Convert to m/s

$\\ \sf\longmapsto 90\times \dfrac{5}{18}$

$\\ \sf\longmapsto 25m/s$

• Time=5min=5×60=300s

We know that

$\boxed{\sf Acceleration=\dfrac{v-u}{t}}$

$\\ \sf\longmapsto Acceleration=\dfrac{25-0}{300}$

$\\ \sf\longmapsto Acceleration=\dfrac{25}{300}$

$\\ \sf\longmapsto Acceleration=0.08m/s^2$