A bicycle travels at 3 m/s over a displacement of 2 km. The rider then changes the bike’s speed instantaneously to a new constant velocity for the next 2 km. A. If the average velocity for the entire 4 km trip is 4 m/s, determine the average velocity of this bike in the last 2 km. (HInt: it isn’t 5 m/s)! B. How much time did the entire trip take?

1000s

Explanation:

Let t1 be time for 2km in 3m/s

t1= 2000/3

And t2 in the next 2km

t2= 2000/v.

So finding the average velocity

4000/t1+t2

=4000/2000(1/3+ 1/v)

V= 6m/s..

For 9km distance in 6m/s

The whole trip is 4m/s

So total time

4000/4=1000s

another example of kinetic energy would be,

kinetic energy   >     moving energy

answer   >   letter choice (c),   a hammer falling off a table.

hope that !                                         : )

no. dot product   =0 when vecs at right angles