A TRAIN WITH AN INITIAL VELOCITY OF 20MS-1 IS SUBJECTED TO A UNIFORM DECELERATION OF 2MS-2. THE TIME REQUIRED TO BRING THE TRAIN TO A COMPLETE HALT IS

• A. 40s
• B. 10s ✓
• C. 20s
• D. 5s

 

The answer to the question is: B. 10s

To find the time required to bring the train to a complete halt, we can use the equations of motion. The equation that relates initial velocity (u), final velocity (v), acceleration (a), and time (t) is:

v = u + at

Where:

v = final velocity

u = initial velocity

a = acceleration

 t = time

In this case, the train’s initial velocity (u) is 20 m/s, and the deceleration (a) is -2 m/s^2 (negative because it’s deceleration). We want to find the time (t) when the final velocity (v) becomes 0 m/s.

Using the equation v = u + at, we can rearrange it to solve for time (t):

0 = 20 + (-2)t

-20 = -2t

 t = 10 s

Therefore, the time required to bring the train to a complete halt is 10 seconds.