Question

a body moving along a straight line at 20 metre per second undergoes an acceleration of -4 metre per second square after 2 second its speed will be

Answer 1

Answer:

Explanation:

INITIAL VELOCITY , U = 20 M/S

ACCELERATION, A = - 4 M/S²

TIME TAKEN , T= 2 SEC

FINAL VELOCITY , V =?

ACCORDING TO NEWTON'S FIRST LAW OF MOTION:

V = U+A T

V = 20-4*2

V = 20-8

V = 12 M/S

FINAL VELOCITY OF THE BODY = 12 M/S.

HOPE THIS HELPS.

Answer 2

Given:

• Initial velocity,u = 20 m/s

• Acceleration, a = -4 m/s² ( negative acceleration)

• Time taken = 2 sec

To be calculated:

Calculate the final velocity( v ) of moving body ?

Formula used :

V = u + at

Solution:

According to the first equation of motion, we have

v = u + at

v = 20 + ( - 4 ) × 2

v = 20 - 8

v = 12 m/s

Thus, final velocity of moving body is 12 m/s.

Additional information:

Acceleration = Rate of increase in velocity.

• initial velocity = u

• Final velocity = v

• Time taken = t

if v > u

Increase in velocity = v - u

Rate of increase in velocity = v - u / t

Acceleration = v - u / t