1.   A car travels along a straight road to the east for 100 meters in 4 seconds, then go the west for 50 meters in 1 second.  
find the
a.  Distance
b.  Displacement
c.  Time elapsed​

a.Distance = 150 m

b. Displacement = 50 m

Time lapsed = 5 seconds

Explanation:

a. Distance is the change in the position of an object.

The distance covered by the car = 100 + 50

                                                   = 150 m

b. Since displacement is a vector quantity,

Displacement of the car = 100 - 50

                                        = 50 m due east

c. Time elapsed is the time taken for the motion of the car starting from when its starts to when it stops.

Thus, the time elapsed = 4 + 1

                        = 5 seconds

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