Question

a particle starts moving with uniform acceleration on a straight line and covers a displacement of 20 m in first two seconds and then it covers a displacement of 30 m in next two seconds. then find initial velocity and acceleration of the particle

Answer 1

Answer:

Initial velocity = 7.5 m/s

acceleration = 2.5 m/s^2

Explanation:

Let initial velocity be u m/s

acceleration be a m/s^2

First case

t=2 s

s=20 m

Using second eq of motion

20 = u(2)+a/2(2^2)

20=2u+2a

u+a=10. -(i)

Second case

t = 4 s

s=50 m

Using second eq of motion

50=u(4)+a/2(4^2)

50=4u+8a

12.5=u+2a. -(ii)

ON SOLVING EQ (i) & (ii)

a=2.5 m/s^2

a=2.5 m/s^2u=7.5 m/s