NCERT Class VII Science Solutions: Chapter 13-Motion and Time Part 3 (For CBSE, ICSE, IAS, NET, NRA 2022)

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Question 11:

Suppose the two photographs, shown in , had been taken at an interval of . If a distance of is shown by in these photographs, calculate the speed of the blue car.

As Showing in Images is a Speed of the Car

Answer:

From the , we conclude that the distance covered by blue car is .

As Showing in Images is a Speed of the Car

So, the distance covered

Question 12:

Fig shows the distance-time graph for the motion of two vehicles A and B. Which one of them is moving faster?

This Diagram Shows Time and Distance Graph

Answer:

Vehicle A is traveling longer distance in lesser time as compared to Vehicle B. So, vehicle A is moving faster.

Question 13:

Which of the following distance-time graphs shows a truck moving with speed which is not constant?

This Diagram Shows Four Different Time-Distance Graphs

Answer:

III. Graph is not a straight line, so it shows a truck moving with speed which is not constant.