Question

the position of a particle moving along x axis is given by x=10t-2t^2.then the time (t) at which it will momently come to rest is
1) zero
2) 2.5
3) 5s
4) 10s

Answer 1

x = 10t - 2t²
Differentiate with dt
v = 10 - 4t
0 = 10 - 4t
t = 2.5 seconds

It will come to rest after 2.5 seconds.

Answer 2

Answer:2.5 sec

Explanation:

x= 10t-2t^2

Differentiation by dt

V=10-4t

As the particle will come to rest it's velocity will be 0

So,

V=10-4t

0=10-4t

t=2.5sec