Question

An object is moving with a velocity of 75 km/h, with an acceleration of 6m/s in the direction opposite to the direction of motion. the time in which the object comes to rest is​

Answer 1

Answer:

The required time taken is 3.472 s.

Explanation:

Given :

An object is moving with a velocity of 75 km/h, with an acceleration of 6m/s in the direction opposite to the direction of motion.

To find :

the time in which the object comes to rest.

Solution :

initial velocity, u = 75 km/h

u = 75 × 5/18 m/s

u = 125/6 m/s

final velocity, v = 0 m/s

Acceleration is acting in the direction opposite to the direction of motion.

a = –6 m/s²

Using v = u + at :

0 = 125/6 + (—6)(t)

6t = 125/6

t = 125/36

t = 3.472 s (approximately)

Answer 2

Answer:

3.47

Explanation:

vf=vi +at

vf=0(as the object comes to rest)

vi=75km/h convert it into m/s bcz acceleration is in m/s so

vi=20.83

a=-6m/s(minus is used bcz direction of motion is opposite)

0=20.83+(-)6(t)

0-20.83=-6t

-20.83/-6=t

t=3.47