Question

The displacement in metres of a body varies with time t in second as y = t2 – t – 2. The displacement is zero for a positive of t equal to

Answer 1

Explanation:

The displacement is given as: y=ut+

2

1

at

2

where, u is the initial velocity and a is the acceleration.

Comparing with given expression: y=16t−2t

2

/3+2,

u=16m/s, a=−

3

4

m/s

2

As, v=u+at, where v is final velocity.

Taking v=0, the time taken for body to come to rest.

0=16−

3

4

t⇒t=12 sec