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3 years ago

10

A car starts from rest and accelerates at a constant rate in a straight line. In the first second the car moves a distance of 2.

0 meters. How fast will the car be moving at the end of the second second

1 answer:

goblinko [34]3 years ago

5 0

Answer:

The speed of the car at the end of the 2nd second = 8.0 m/s

Explanation:

The equations of motion will be used to solve this problem.

A car starts from rest,

u = initial velocity of the car = 0 m/s

Accelerates at a constant rate in a straight line,

a = constant acceleration of the car = ?

In the first second the car moves a distance of 2.0 meters,

t = 1.0 s

x = distance covered = 2.0 m

x = ut + (1/2)at²

2 = 0 + (1/2)(a)(1²)

a = 4.0 m/s²

How fast will the car be moving at the end of the second second

Now,

a = 4.0 m/s²

u = initial velocity of the car at 0 seconds = 0 m/s

v = final velocity of the car at the end of the 2nd second = ?

t = 2.0 s

v = u + at

v = 0 + (4×2)

v = 8.0 m/s

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