Avan slows down as it travels up a steep hill. its speed goes from 20m/s at the bottom of the hill to 12m/s when it reaches the top 8 seconds later. how far has the van travelled between the bottom and the top of the hill?

Answer

13.06 m

Explanation

The height reach ca be calculated using the one of the linear equation.

v² = u² - 2gs

where u ⇒ is the initial speed,

          v ⇒ is the final speed

        g ⇒ is the acceleration due to gravity and

       s ⇒ the height reached.

v² = u² - 2gs

12² = 20² - (2×9.8×s)

144 = 400 - 19.6s

19.6s = 400 - 144

        = 256

s = 256/19.6

    = 13.06 m

d = 128 m

Explanation:

Here given that van slows down as it travels up a inclined steep hill

So here we can assume that through out the motion its acceleration will remain constant.

Now we can use kinematics to find out the distance traveled by it

As we know that acceleration is defined as

here we know that

time = 8 s

now we have

Now in order to find out the distance it moved we can use

now we will plug in all above data

so it will cover total distance of 128 m

the part of the wave he is travelling on is the crest

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.