SEBA Class 7 Science Chapter 4 Motion and Time – Textbook Solutions & MCQ (Part I)
Get Class 7 Science Chapter 4 “Motion and Time” Solutions for SEBA Assam (English Medium) students. This chapter, from Part I of the Science book, explains the concepts of motion, types of motion, measurement of time, speed, velocity, and distance-time graphs. Our solutions provide detailed NCERT/SCERT textbook answers, important MCQs, and key explanations to help students understand the fundamental concepts of motion and time. These solutions are structured to make learning easy and effective for exam preparation.
Class 7 Science
Chapter – 4 (Part I) Ospin Academy
Motion and Time
EXERCISE
Q. 1. Classify the following as motion along a straight line, circular or oscillatory motion:
(i) Motion of your hands while running.
Ans: Oscillatory.
(ii) Motion of a horse pulling a cart on a straight road.
Ans: Along a straight line.
(iii) Motion of a child in a merry go round.
Ans: Circular.
(iv) Motion of a child on a see-saw.
Ans: Oscillatory.
(v) Motion of the hammer of an electric bell.
Ans: Oscillatory.
(vi) Motion of a train on a straight bridge.
Ans: Along a straight line.
Q. 2. Which of the following are not correct?
(i) The basic unit of time is second.
(ii) Every object moves with a constant speed.
(iii) Distance between two cities are measured in kilometers.
(iv) The time period of a given pendulum is not constant.
(v) The speed of a train is expressed in m/h.
Ans: (ii), (iv), (v).
Q. 3. A simple pendulum takes 32s to complete 20 oscillations. What is the time period of the pendulum?
Ans: Time period of a pendulum is time taken to complete 1 oscillation.
Time taken to complete 20 oscillations = 32s
Time taken to complete 1 oscillation
∴ Time period of pendulum is 1.6 seconds.
Q. 4. The distance between two stations is 240 km. A train takes 4 hours to cover this distance. Calculate the speed of the train.
Ans: Distance = 240 km.
Time taken = 4 hr.
Speed of the train is 60 km/h.
Q.5. The odometer of a car reads 57321.0 km when the clock shows the time 08:30 AM. What is the distance moved by the car, if at 08:50 AM, the odometer reading has changed to 57336.0 km? Calculate the speed of the car in km/min during this time. Express the speed in km/h also.
Ans. Distance = 57336.0 km – 57321 km
= 15 km
Time = 8.50 AM. – 8.30 AM
= 20 min
Q. 6. Salma takes 15 minutes from her house to reach her school on a bicycle. If the bicycle has a speed of 2 m/s., calculate the distance between her house and the school.
Ans. Time taken = 15 min
Speed = 2 m/s.
Distance = speed x time
= 15 x 2 = 30 m.
So, distance between Salma’s school and her house is 30 meters.
Q. 7. Show the shape of the distance- time graph for the motion in the following cases:
(i) A car moving with a constant speed.
(ii) A car parked on a side road.
Ans:
Fig. 13. 18.
Q. 8. Which of the following relations is correct?
(i) Speed = Distance x Time
Q. 9. The basic unit of speed is:
(i) km/min
(ii) m/min
(iii) km/h
(iv) m/s.
Ans: (iv) m/s.
Q. 10. A car moves with a speed of 40 km/h for 15 minutes and then with a speed of 60 km/h for the next 15 minutes. The total distance covered by the car is:
(i) 100 km
(ii) 25 km
(iii) 15 km
(iv) 10 km
Ans: (ii) 25 km.
Q. 11. Suppose the two photographs shown in Fig. 13.19 and 13.20, had been taken at an interval of 10 seconds. If a distance of 100 meters is shown by 1 em in these photographs, calculate the speed of the blue car.
Fig. 13.19. Vehicles moving in the same direction on a road.
Ans. 0.1 cm/s or 10m/s.
Fig. 13.20. Position of vehicles shown in Fig. 13.19 after some time.
Q. 12. Fig. 13.21 shows the distance-time graph for the motion of two vehicles A and B. Which one of them is moving faster?
Fig. 121. Distance-time graph for the motion of two cars.
Ans: ‘A’ car is moving faster.
Q. 13. Which of the following distance-time graphs shows a truck moving with speed which is not constant?
Fig. 13.22
Ans: (iii)
FAQs – Class 7 Science Chapter 4 (Motion and Time, SEBA Assam)
Q1: What are the different types of motion in physics?
Motion is classified as uniform motion, non-uniform motion, periodic motion, and random motion.
Q2: How is speed calculated in motion and time?
Speed = Distance ÷ Time and is measured in m/s or km/h.
Q3: What is the importance of a pendulum in measuring time?
The simple pendulum helps measure time intervals based on oscillations.
Q4: Where can I find Class 7 Science Chapter 4 solutions for SEBA Assam?
You can find detailed textbook solutions, MCQs, and explanations for SEBA Assam Class 7 Science Chapter 4 on this page.
Q5: Where can I find solutions for all Class 7 Science chapters?
To get solutions for all Class 7 Science chapters, Click Here
