Advertisements
Advertisements
Question
A train moving with a velocity of 20 ms−1 is brought to rest by applying brakes in 5 s. Calculate the retardation.
Advertisements
Solution
Given:
-
Initial velocity, u = 20 m/s
-
Final velocity, v = 0 m/s (since train comes to rest)
-
Time, t = 5 s
0 = 20 + a × 5
0 = 20 + 5a
5a = −20
a = −4m/s2
Retardation = 4 m/s2
APPEARS IN
RELATED QUESTIONS
Draw a graph for acceleration against time for a uniformly accelerated motion. How can it be used to find the change in speed in a certain interval of time?
Figure given below shows a velocity-time graph for a car starting from rest. The graph has three parts AB, BC and CD.

Which part of graph shows motion with uniform
(a) velocity (b) acceleration (c) retardation ?
Draw velocity – time graph for the following situation:
When a body is moving with variable velocity and variable acceleration.
A racing car is moving with a velocity of 50 m/s. On
applying brakes, it is uniformly retarded and comes to rest in 20 seconds. Calculate its acceleration.
From the velocity – time graph given below, calculate deceleration in region BC.

State if the following situation is possible:
A body moving horizontally with an acceleration in vertical direction.
What happens to the stepwise increasing speed-time graph when the size of each step is made very small?
Convert the following acceleration:
7200 km/h2 into m/s2
Negative acceleration is called ______.
The acceleration of the body that moves with a uniform velocity will be ______.
