Question

10.
The velocity acquired by a body moving with uniform acceleration is 30 m/s in 2 seconds and 60 m/s in
4 seconds. The initial velocity is
(A) zero
(B) 2 m/s
(C)4 m/s
(D) 10 m/s​

Answer 1

Answer:

Now,

at t = 2s, v = 30m/s

at t = 4s, v = 60 m/s

so, acceleration

a = dv / dt = (60-30) / (4-2)

thus,

a = 30/2 = 15m/s

now,

v = u +at

initial velocity will be calculated using

u = v - at

after two seconds

u = 30 - 15 × 2

thus, initial velocity

u = 0m/s.

hope this help...

Answer 2

hii dear !!

formula of initial velocity is calculated by u is equal by = u + a * t.

here is 30 m/s , v is 60 m/s

T is difference in time, that is 4 s 2 , that is 2 sec

implies u = v - at

= 30 - 15 * 2

u = 0 m/s.

I hope help you