Page 115 - Ripples SCIENCE 7 - TEJPUR Edition 2024 Answer Key

Exercise

A. Tick (3) the correct answer.

1. If we denote speed by S, distance by D and time by T, the relationship between these
quantities is .................... .

(a) S = D × T (b) T = S/D (c) S = D/T (d) S = T/D
Ans: (c)

2. The correct unit to represent the speed of an object is .................... .

(a) m/s (b) ms (c) m/s-1 (d) s/m
Ans: (a)

3. A faster moving object covers more distance in .................... time.
(a) Less (b) More (c) Equal (d) None of the above

Ans: (a)
4. A pendulum takes 0.5 s to make one oscillation about its mean position. How long

will it take to make 5 oscillations?

(a) 5 s (b) 7.5 s (c) 2.5 s (d) 10 s
Ans: (c)

5. A truck travels 136 km in 8 hours. What is the speed of the truck?
(a) 15 km/h (b) 18 km/h (c) 13 km/h (d) 17 km/h

Ans: (d)
6. Name the type of motion described by an arrow when it is released from a bow.

(a) Curvilinear motion (b) Rectilinear motion

(c) Periodic motion (d) Oscillatory motion
Ans: (a)

B. Fill in the blanks.
1. SI unit of distance is ..................... .

Ans: metre (m)
2. The exact path traversed by the body is called the ..................... covered by the body.

Ans: distance

3. The motion of our hands while running is called ..................... .
Ans: periodic motion

4. The motion of a child on a merry-go-round is called ..................... .
Ans: circular motion

5. ..................... is the period of time between two events.
Ans: Interval

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