# NCERT Class VII Science Solutions: Chapter 13-Motion and Time Part 3

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**VERY SHORT ANSWER QUESTIONS**

**Question 10:**

A simple pendulum is oscillating between two points A and B as shown in Figure. Is the motion of the bob uniform or non - uniform?

**Answer:**

The motion of bob is non – uniform, as it does not cover equal intervals of time.

**Question 11:**

Paheli and Boojho have to cover different distances to reach their school but they take the same time to reach the school. What can you say about their speed?

**Answer:**

They do not have equal speed because they cover unequal distances in equal intervals of time. One of them has higher speed, whom has to cover larger distance with respect to other.

**Question 12:**

If Boojho covers a certain distance in one hour and Paheli covers the same distance in two hours, who travels in a higher speed?

**Answer:**

Boojho moves at a higher speed as he covers the same distance in a lesser time than Paheli.

**SHORT ANSWER QUESTIONS**

**Question 13:**

Complete the data of the table given below with the help of the distance-time graph given in Figure

| 0 | 4 | ? | 12 | ? | 20 |

| 0 | 2 | 4 | ? | 8 | 10 |

**Answer:**

| 0 | 4 |
| 12 |
| 20 |

| 0 | 2 | 4 |
| 8 | 10 |

**Question 14:**

The average age of children of Class VII is 12 years and 3 months. Express this age in seconds.

**Answer:**

12 years 3 months