Acceleration is a change in *speed* over time. In this case, the speed of the car increased by 90 km/hr in 6 s, giving it a rate of 90 km/hr/6s, or 15 km/hr/s. We’re asked for the acceleration in m/s^2, though, so we’ll need to do a few conversions to get our units straight.

There are 1000 m in 1 km, 60 min, or 60 * 60 = 3600 s in 1 hr, so we can change our rate to:

(15 x 1000)m/3600s/s, or (15 x 1000)m/3600 s^2

We can reduce this to:

(15 x 10)m/36 s^2 = 150 m/36 s^2

Which, dividing numerator and denominator by 36, gets us a final answer of roughly 4.17 m/s^2

3 0

3 years ago

A car starts from rest and travels for 5.8 s with a uniform acceleration of 1.6 m/s² in the negative direction. What is the fina

elena-s [515]

Answer:

Final velocity of the car will be -9.28 m/sec

Explanation:

We have given that the car starts from the rest so initial velocity of the car u = 0 m /sec

Acceleration of the car $a=1.6m/sec^2$ in negative direction so acceleration will be $a=-1.6m/sec^2$

From first equation of motion we know that

v = u+at

So $v=0+(-1.6)\times 5.8=-9.28m/sec$

So final velocity will be -9.28 m/sec

8 0

3 years ago

A boy throws a ball and accidentally breaks a window. The momentum of the ball and all the pieces of glass taken together after

geniusboy [140]

A boy throws a ball and accidentally breaks a window. The momentum of the ball and all the pieces of glass taken together after the collision is the same as <span>the momentum of the ball before the collision. I think you forgot to give the choices along with the question. I hope that the answer has come to your great help.</span>

3 0

3 years ago