Question

A body travels 10 m in first three seconds and
15 m in the next four seconds. What is the
velocity at the end of 8 second?​

Answer 1

Answer:

A body travels 10 m in the 1st 3 seconds and 15 m in the next 4 seconds. What is the velocity at the end of 8 seconds?

From 2021, PG entrance will test your clinical concepts.

Let u be initial velocity and a be uniform acceleration .

For motion in first 3s, we have,

10=3u+(1/2)a(9) …………(1)

For motion in first (3+4)s

25=3u+(1/2)a(49)…………(2)

(2)-(1) gives

15=(1/2)a(40)=20a OR

a=3/4 m/s^2……….(3)

Using this value in (1)

10=3u+(1/2)(3/4)(9)

10= 3u+(27/8) Therefore,

u=(53/24) m/s

The velocity at the end of 8s,

v=u+at

v=(53/24)+(3/4)(8)=[ (53/24)+6]m/s