8.
A particle starts from rest. Its acceleration is
varying with time as shown in the figure. When the
particle comes to rest, its distance from its starting
point is
a (m/s)
24
La § st(s)
2
(1) 20 m
(3) 36 m
(2) 24 m
(4) 14 m
Answers
Answer:14
Step-by-step explanation:
Answer:
4th option is correct.
Step-by-step explanation:
Given:
A graph with acceleration on y-axis and time on x-axis.
To find: Distance covered between from its starting point to point when object comes to rest.
Firstly, for first 2 seconds,
acceleration, a = 2 m/s² , initial speed , u = 0 m\s and time, t = 2 second
using following formula,
s = ut + 1/2 at²
s = 0 × 2 + 1/2 × 2 × 2²
s = 4 m
Secondly, for next 2 seconds,
acceleration, a = 0 m/s² ⇒ velocity is constant ⇒ u = 4m/s and time, t = 2 second
using following formula,
s = ut + 1/2 at²
s = 4 × 2 + 1/2 × 0 × 2²
s = 8 m
Finally, for last 2 seconds,
acceleration, a = -4 m/s² , final velocity , v = 0 m\s , initial velocity, u = 4 m/s and time, t = 2 second
using following formula,
v² - u² = 2as
0² - 4² = 2(-4)s
-16 = -8s
s = 2 m
Total Distance covered = 4 + 8 + 2 = 14 m
Therefore, 4th option is correct.