Question

If an object moves such that its acceleration changes according to a = 8t – 1, then find velocity of object at 10s. Also find the distance covered by the object in 5s.

Answer 1

Answer:

v = u + at

After 5s

25 = u + 5a ——(1)

After 8s

34 = u + 8a ——(2)

Subtract equation (1) from equation (2)

34 - 25 = u + 8a - u - 5a

9 = 3a

a = 3 m/s^2

Substitute a = 3m/s^2 in equation (1)

25 = u + 5*3

u = 10 m/s

Distance travelled in 12th second

S = u + a(n - 1/2)

S = 10 + 3*(12 - 1/2)

S = 44.5m

Distance travelled in 12th second is 44.5m