The velocity of a particle at an instant is 10 m s-1. After 3 s its velocity will become 16 m s-1. The velocity at 2 s, before the given instant will be

Question

The velocity of a particle at an instant is 10 m s-1. After 3 s its velocity will become 16 m s-1. The velocity at 2 s, before the given instant will be (A) 6 m s-1 (B) 4 m s-1 (C) 2 m s-1 (D) 1 m s-1

Tardigrade Admin · Accepted Answer

Here, u = 10 m s-1, t = 3 s, v = 16 m s-1 a=(v-u/t)=(16-10/3)=2 m s-2 Now velocity at 2 s, before the given instant 10=u+2× 2 ∴ u=6 m s-1 (∵ v=u+at)

Q. The velocity of a particle at an instant is $10 m s^{- 1}$ . After $3 s$ its velocity will become $16 m s^{- 1}$ . The velocity at $2 s$ , before the given instant will be

$6 m s^{- 1}$

$4 m s^{- 1}$

$2 m s^{- 1}$

$1 m s^{- 1}$

Here, $u = 10 m s^{- 1}$ , $t = 3 s$ , $v = 16 m s^{- 1}$
$a = \frac{v - u}{t} = \frac{16 - 10}{3} = 2 m s^{- 2}$
Now velocity at $2 s$ , before the given instant
$10 = u + 2 \times 2$
$∴ u = 6 m s^{- 1} (∵ v = u + a t)$

Q. The velocity of a particle at an instant is 10ms−1. After 3s its velocity will become 16ms−1. The velocity at 2s, before the given instant will be

6ms−1

4ms−1

2ms−1

1ms−1