A man runs 400.0m around the track, then another 400.0m around the track again.
As the track is 400.Om long, the man is back
where he started!
a) calculate distance travelled

b) calculate mans displacement

Distance = 800 m, Displacement = 0

Explanation:

It is given that,

A man runs 400 m around the track,  then another 400 m around the track again.

(a) Distance travelled by an object is the sum of total path covered.

In this case, he has covered total path of 400 m + 400 m i.e. 800 m. It means he travelled a distance of 800 m.

(b) Displacement covered by an object is the shortest path covered by it. In this problem, he reaches the point from where he has started. It means that his displacement is equal to 0.

spectral lines lyman is one set

54 degrees incident angle = reflected angle

angle is from normal turned to line of ray