Question

A train starting from rest aquires a velocity of 54km/pr in 20 sec . Cal ulate the acceleration and distance travelled by it

Answer 1

Hello Friend,

Here,

→ The train starts from rest. This means that initial velocity must be zero. Next, we need to convert all units into SI units. So, we will convert 54 km/h into m/s

Initial velocity = u = 0 m/s
Final velocity = v = 54 km/h = 15 m/s
Time = t = 20 s

Let acceleration be a.
Let distance travelled be s.

→ Now, motion is uniformly accelerated. So,

v = u + at
So, 15 = 0 + a(20)
So, a = 15/20 m/s²
So, a = ¾ m/s²
Or, a = 0.75 m/s²

→ Now, to find the distance travelled,

s = ut + ½ at²
So, s = (0)(20) + (½)(¾)(20)²
So, s = ⅜ × 400
So, s = 150 m

→ Thus, acceleration is 0.75 m/s² and distance travelled is 150 metres.

Hope it helps.

Purva
@Purvaparmar1405
Brainly.in