Question

A particle starts from rest with an acceleration 2m * s ^ - 2 . If the force producing acceleration is applied for 10 s then determine the velocity of the particle after 20 s. (a) 40m * s ^ - 1 (c) 20m * s ^ - 1 (b) 10m * s ^ - 1 (d) 30m * s ^ - 1​

Answer 1

Given:-

• Initial velocity ,u = 0m/s
• Acceleration ,a = 2m/s²
• Time taken ,t = 20 s

To Find :-

• Final velocity ,v

Solution:-

⠀⠀⠀⠀⠀⠀⠀⠀⠀According to the Question

It is given that the particles start from rest & accelerate at 2m/s² . We have to calculate the final velocity of particles after 20s . Using 1st equation of motion

• v = u + at

where,

• v denote final velocity
• u denote initial velocity
• a denote acceleration
• t denote time taken

Substitute the value we get

$:\implies$ v = 0 + 2×20

$:\implies$ v = 0 + 40

$:\implies$ v = 40 m/s

• Hence, the final velocity of the particles is 40m/s

So ,the required option is (a) 40m/s .

Answer 2

Given :-

A particle starts from rest with an acceleration 2 m/s². If the force producing acceleration is applied for 10 s then determine the velocity of the particle after 20 s.

To Find :-

then determine the velocity of the particle after 20 s

Solution :-

We know that

v = u + at

v = 0 + 2(20)

v = 0 + 40

v = 40

Hence,

Final velocity is 40 m/s