📝 What about 1-Mark Questions?
The 1-mark MCQs are covered separately in the Chapter-wise MCQ Test. So, this page focuses on 2, 3, 4 and 5-mark exam questions, while the 1-mark preparation is done through the MCQ test.
🎯 Go to 1-Mark MCQ Test →
2 Marks Questions
Q1. What is a simple pendulum? What is meant by one oscillation?
Answer:
A simple pendulum consists of a small metallic ball (bob) suspended from a rigid support by a long thread. One complete motion O → A → B → O is one oscillation.
Q2. Define the time period of a pendulum. How is it found experimentally?
Answer:
The time taken by a pendulum to complete one oscillation is called its time period. Measure the time for several oscillations and divide the total time by the number of oscillations.
Q3. State the SI unit of time. Write the symbols of minute and hour.
Answer:
The SI unit of time is second (s). Minute and hour have the symbols min and h.
Q4. Define speed and write its formula.
Answer:
Speed = Total distance covered ÷ Total time taken.
Q5. What is uniform linear motion? Give one example.
Answer:
An object moving along a straight line with constant speed is in uniform linear motion. A train moving along a straight track with constant speed is an example.
Q6. What is non-uniform linear motion?
Answer:
If the speed of an object moving along a straight line keeps changing, its motion is non-uniform linear motion.
Q7. A car travels 150 m in 10 s. Calculate its speed.
Answer:
Speed = 150 ÷ 10 = 15 m/s.
Q8. Two runners cover 400 m in 50 s and 45 s respectively. Who has the greater speed?
Answer:
The second runner has the greater speed because both cover the same distance but the second runner takes less time.
Q9. Which types of devices were used by people in earlier times to measure time? Give four examples.
Answer:
People used sundials, water clocks, hourglasses and candle clocks to measure time.
Q10. Why did people observe natural events such as the rising and setting of the Sun, phases of the Moon and changing seasons?
Answer:
They observed these regularly repeating events because their cycles helped people keep track of time.
3 Marks
Q1. A train travels at 25 m/s and covers 360 km. Calculate the time taken.
Answer:
360 km = 360,000 m. Time = 360,000 ÷ 25 = 14,400 s = 4 h.
Q2. A train travels 180 km in 3 h. Find its speed in km/h and m/s. Also find the distance travelled in 4 h at the same speed.
Answer:
Speed = 180 ÷ 3 = 60 km/h = 16.67 m/s approximately. Distance in 4 h = 60 × 4 = 240 km.
Q3. How does the length of a simple pendulum affect its time period? Does the mass of its bob affect the time period?
Answer:
The time period depends on the length of the simple pendulum. For a given length at a place it is constant. It does not depend on the mass of the bob.
Q4. Distinguish between uniform and non-uniform linear motion.
Answer:
Uniform linear motion: equal distances in equal time intervals along a straight line. Non-uniform linear motion: unequal distances in equal time intervals along a straight line.
Q5. Train X covers 20 km in every 10-minute interval. Train Y covers 20, 15, 15, 25, 20 and 25 km in successive 10-minute intervals. Which has uniform linear motion and why?
Answer:
Train X has uniform linear motion because it covers equal distances in equal time intervals. Train Y has non-uniform linear motion.
Q7. Why is total distance divided by total time called average speed when speed changes during a journey?
Answer:
The object may move faster or slower during different parts of the journey. Total distance ÷ total time gives the average speed for the complete journey.
Q6. Compare a horse moving at 18 m/s with a train moving at 72 km/h.
Answer:
72 km/h = 20 m/s. The train is faster by 2 m/s.
4 Marks — Case-Based Study
Case Study 1 — Simple pendulum
A student sets up a simple pendulum using a bob, thread, rigid support and stopwatch. The bob is displaced slightly from its mean position and released. The student measures the time for 10 oscillations several times and obtains nearly similar readings. The student then repeats the activity with a longer thread.
QuestionsFirst: What is one oscillation?
Second: What is the time period?
Third: Why are several oscillations measured?
Fourth: What happens to the time period when the length is increased?
AnswersFirst: One complete to-and-fro motion, such as O → A → B → O, is one oscillation.
Second: The time taken to complete one oscillation is the time period.
Third: Several oscillations give a more reliable value because the total time is divided by the number of oscillations.
Fourth: The time period increases when the length of the simple pendulum is increased.
Case Study 2 — Two trains
Two trains travel from 10:00 AM to 11:00 AM. Train X covers 20 km in every 10-minute interval. Train Y covers 20, 15, 15, 25, 20 and 25 km in successive 10-minute intervals.
QuestionsFirst: Which train shows uniform linear motion?
Second: Which train shows non-uniform linear motion?
Third: Why is Train X uniform?
Fourth: What is the condition for uniform linear motion?
AnswersFirst: Train X.
Second: Train Y.
Third: It covers equal distances in equal time intervals.
Fourth: An object moving along a straight line covers equal distances in equal intervals of time.
Case Study 3 — Speed calculation
A cyclist covers 3.6 km in 15 minutes. A second cyclist moves at 5 m/s. Compare their speeds.
QuestionsFirst: Convert 3.6 km into metres.
Second: Convert 15 minutes into seconds.
Third: Calculate the first cyclist's speed.
Fourth: Which cyclist is faster?
AnswersFirst: 3.6 km = 3600 m.
Second: 15 min = 900 s.
Third: Speed = 3600 ÷ 900 = 4 m/s.
Fourth: The second cyclist is faster because 5 m/s > 4 m/s.
Case Study 4 — Vehicle on a straight road
A vehicle starts slowly, increases its speed, then moves at constant speed for some distance and finally slows down and stops at the next station.
QuestionsFirst: What is the motion called when an object moves along a straight line?
Second: What type of motion occurs during the constant-speed part?
Third: What type occurs while the speed changes?
Fourth: What happens to distances covered in equal time intervals during non-uniform linear motion?
AnswersFirst: The motion is called linear motion.
Second: Uniform linear motion.
Third: Non-uniform linear motion.
Fourth: Unequal distances are covered in equal time intervals.
Case Study 5 — Average speed
A car covers 60 km in the first hour, 70 km in the second hour and 50 km in the third hour.
QuestionsFirst: Are the distances equal in equal time intervals?
Second: Is the motion uniform or non-uniform?
Third: Find the total distance.
Fourth: Find the average speed.
AnswersFirst: No. The distances are different.
Second: Non-uniform.
Third: 60 + 70 + 50 = 180 km.
Fourth: Average speed = 180 ÷ 3 = 60 km/h.
5 Marks
Q1. A car covers 60 km in the first hour, 70 km in the second hour and 50 km in the third hour. Is its motion uniform? Justify and find its average speed.
Answer:
No. It covers unequal distances in equal one-hour intervals, so its motion is non-uniform. Total distance = 180 km; total time = 3 h; average speed = 180 ÷ 3 = 60 km/h.
Q2. A vehicle covers 2 km. In the first 500 m it moves at 10 m/s and in the next 500 m at 5 m/s. The complete journey takes 200 s. Find the speed for the remaining distance and the average speed.
Answer:
Remaining distance = 1000 m. First time = 50 s; second time = 100 s; remaining time = 50 s. Required speed = 1000 ÷ 50 = 20 m/s. Average speed = 2000 ÷ 200 = 10 m/s.
Q3. An object has the following data: Time (s): 0, 10, 20, 30, 50, 70; Distance (m): 0, 8, 24, 32, 40, 56. If it is in uniform motion, fill the missing values and explain.
Answer:
For uniform motion, the distance covered in equal time intervals must be equal. The given sequence must therefore be checked by comparing each time interval; the required values are obtained by maintaining the same distance increase per equal interval.
Q4. Fill in the blanks.
(A) The SI unit of time is ________.
(B) The time taken for one oscillation is called the ________.
(C) Speed = total distance covered ÷ total ________ taken.
(D) Equal distances in equal intervals of time along a straight line indicate ________ linear motion.
(E) The instrument that measures and displays a vehicle's speed is called a ________.
Answers:
(A) second (s)
(B) time period
(C) time
(D) uniform
(E) speedometer
Q5. Match the columns correctly.
Column A
A. Simple pendulum
B. Time period
C. Speed
D. Uniform linear motion
E. Odometer
Column B
1. Measures distance travelled by a vehicle
2. Total distance divided by total time
3. Time taken for one oscillation
4. Equal distances in equal intervals of time along a straight line
5. Bob suspended by a thread from a rigid support
Answer: A–5, B–3, C–2, D–4, E–1.
Q6. Three runners complete 400 m in 50 s, 400 m in 45 s and 200 m in 20 s. Calculate each speed and identify the highest speed.
Answer:
Runner 1 = 8 m/s. Runner 2 = 400 ÷ 45 ≈ 8.89 m/s. Runner 3 = 10 m/s. The third runner has the highest speed.
Q7. A train travels 180 km in 3 h and another 60 km in 1 h. Find total distance, total time and average speed. Can average speed alone prove uniform motion?
Answer:
Total distance = 240 km. Total time = 4 h. Average speed = 240 ÷ 4 = 60 km/h. No. Average speed alone cannot prove uniform motion because speed may vary during the journey.