Class 7 Science Measurement of Time and Motion Worksheet

Measurement of time and motion are two fundamental concepts that help us make sense of the world around us. From waking up in the morning to catching a bus or participating in a race, every part of our daily life involves the use of time and motion.

Have you ever wondered how did people measure time before the invention of watches and clocks? How do we compare which object is moving faster or slower? This chapter takes us on an exciting journey through the evolution of timekeeping methods—from sundials and water clocks to modern atomic clocks.

This chapter explains the fascinating science of motion. It teaches you what speed is, how to calculate it, and how to distinguish between uniform and non-uniform motion.

Measurement of Time and Motion Worksheet

Through engaging activities and real-life examples like pendulums, races, and vehicles, this chapter helps you understand how motion is measured and compared. Whether it’s the ticking of a clock or the speed of a runner, the science behind measuring time and motion is both practical and amazing! Our worksheet covers variety of question types like fill in the blanks, MCQs, Question – Answer and numerical problems to help you learn about time measurement, and speed.

Also download:
Class 7 Science Worksheet Curiosity
Class 7th Science NCERT Solutions Curiosity

Science Class 7 Measurement of Time and Motion Notes

Measurement of Time

• Timekeeping began with observation of natural events (sunrise, sunset, moon phases).
• Ancient time devices: Sundials, water clocks, hourglasses, candle clocks.
• Pendulum clock: Invented by Christiaan Huygens in 1656; based on Galileo’s observations.
• Simple pendulum: A bob tied to a thread. One oscillation = mean → one extreme → other extreme → mean.
• Time period: Time to complete one oscillation. Depends on the length, not mass.
• SI Unit of Time: Second (s). Other units: minute (min), hour (h).
• Modern clocks: Use quartz crystals or atomic vibrations for high precision.

Slow or Fast

• Speed helps compare fast/slow motion.
• Faster objects cover more distance in the same time.

Speed

• Speed = Distance / Time
• SI unit: m/s; other: km/h.
• Average speed is used when speed is not constant.

Time and Motion Question Answer

Q1. What is a stopwatch and where is it used?
A: A stopwatch is a device used to measure short time intervals precisely. It is commonly used in sports events to time races and athletic performances.

Q2. What is the function of a pendulum in clocks?
A: A pendulum provides a consistent time interval through its oscillations, which helps in accurate timekeeping in pendulum clocks.

Q3. Why are atomic clocks considered very accurate?
A: Atomic clocks measure time based on the vibrations of atoms, which are extremely consistent, allowing them to lose only one second in millions of years.

Q4. What is meant by average speed?
A: Average speed is the total distance covered divided by the total time taken, especially when the speed varies during motion.

Q5. Why do we need accurate measurement of time in sports?
A: Because in sports, results can depend on differences of a fraction of a second, accurate timing helps determine winners fairly.

Q6. How is time measured in modern devices?
A: Modern clocks measure time using periodic vibrations of quartz crystals or atoms in atomic clocks.

Time Motion and Speed Class 7 Numericals

Q1. A car covers 240 km in 4 hours. What is its speed?
Solution:
Speed = Distance / Time = 240 km / 4 h = 60 km/h

Q2. A train travels at a speed of 72 km/h. How much distance will it cover in 3 hours?
Solution:
Distance = Speed × Time = 72 × 3 = 216 km

Q3. A cyclist covers 15 km in 50 minutes. Find the speed in m/s.
Solution:
Convert distance: 15 km = 15,000 m
Time = 50 × 60 = 3000 s
Speed = 15000 / 3000 = 5 m/s

Q4. A pendulum completes 20 oscillations in 32 seconds. Find its time period.
Solution:
Time period = Total time / No. of oscillations = 32 / 20 = 1.6 s

Q5. A train travels 120 km at 60 km/h and then 180 km at 90 km/h. What is its average speed for the entire journey?
Solution:
Time for 1st part = 120 / 60 = 2 h
Time for 2nd part = 180 / 90 = 2 h
Total distance = 120 + 180 = 300 km
Total time = 2 + 2 = 4 h
Average speed = 300 / 4 = 75 km/h

Q6. A runner completes a 400 m track in 52 s. In the next round, he takes 58 s. What is his average speed?
Solution:
Total distance = 400 + 400 = 800 m
Total time = 52 + 58 = 110 s
Average speed = 800 / 110 = 7.27 m/s