The automobile beltway around many cities is approximately circular. suppose that you start driving at point a on the east side of the beltway and drive counterclockwise at an unchanging 90 km/hr (figure 3.13). as you pass point b on the north side, what is your speed? your velocity?

speed is the magnitude of velocity which is given as 90 km/hr and it does not change. only the direction change , the direction at any time is given by the tangent to the circle at that time and location.

from the diagram , at north side, the velocity is directed in west direction

energy can be converted from one form to another, but it cannot be created or destroyed in ordinary chemical or physical means. do not understand what you are asking but hope this