Question

Question 53:
The graph given alongside shows the positions of a body at different times. Calculate the speed of the body as it moves from :
(i) A to B,
(ii) B to C, and
(iii) C to D.


Lakhmir Singh Physics Class 9

Answer 1

Answer:

(i) Speed from A to B = 1 cm/s

(ii) Speed from B to C = 0

(iii) Speed from C to D = 2 cm/s

Explanation:

The graph is attached

From A to B the graph is a straight line, from B to C it is a horizontal line parallel to the time axis and from C to D it is again a straight line

Distance covered from A to B = 3-0 = 3 cm

Time taken from A to B = 5-2 = 3 seconds

Therefore speed from A to B = Distance/ Time = 3/3 = 1 cm/s

Distance covered from B to C = 3-3 = 0 cm

Time taken from B to C = 7-5 = 2 seconds

Therefore speed from B to C = Distance/ Time = 0/2 = 0

Distance covered from C to D = 7-3 = 4 cm

Time taken from C to D = 9-7 = 2 seconds

Therefore speed from C to D = Distance/ Time = 4/2 = 2 cm/s