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Boojho goes to the football ground to play football. The distance-time graph of his journey from his home to the ground is given in the figure. What does the graph between points B - Science

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Question

Boojho goes to the football ground to play football. The distance-time graph of his journey from his home to the ground is given in the figure.

  1. What does the graph between points B and C indicate about the motion of Boojho?
  2. Is the motion between 0 to 4 minutes uniform or non-uniform?
  3. What is his speed between 8 and 12 minutes of his journey?
Graph
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Solution

a. Graph between points B and C is a horizontal line which indicates that Boojho is at rest, i.e., his speed is zero.

b. Motion between 0 to 4 minutes is non-uniform as distance-time graph for this time interval is not a straight line.

c. Speed of Boojho between 8 and 12 minutes of his journey

= `((225 - 150)  "m")/((12 - 8)  "min")`

= `75/4`

= 18.75 m/min

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Chapter 13: Motion and Time - LONG ANSWER QUESTIONS [Page 74]

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NCERT Exemplar Science [English] Class 7
Chapter 13 Motion and Time
LONG ANSWER QUESTIONS | Q 20. | Page 74

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