Question

a body moving along a straight line at 20 m/s undergoes an acceleration of -4m/s 2after two second its speed will be​

Answer 1

Answer:

v=12m/s

Explanation:

v=u+at

v=20+(-4)(2)

v= 20-8

v=12m/s

Answer 2

Answer:

Explanation:

Solution,

Here, we have

Initial velocity, u = 20 m/s

Acceleration, a = - 4 m/s²

Time taken, t = 2 seconds

To Find,

Final velocity, v = ??

According to the 1st equation of motion,

We know that,

v = u + at

So, putting all the values, we get

⇒ v = u + at

⇒ v = 20 + (- 4) × 2

⇒ v = 20 - 8

⇒ v = 12 m/s

Hence, the speed after 2 seconds will be 12 m/s.