Measurement of Time and Motion Class 7 MCQ
hardMeasurement of Time and Motion Class 7 MCQ
Measurement of Time and Motion Class 7 MCQ
Question 1.
Who invented the pendulum clock?
(a) Galileo Galilei
(b) Isaac Newton
(c) Christiaan Huygens
(d) Albert Einstein
Answer:
(c) Christiaan Huygens
Question 2.
Which of the following is NOT a traditional time-measuring device?
(a) Sundial
(b) Water clock
(c) Pendulum clock
(d) Stopwatch
Answer:
(d) Stopwatch
Question 3.
The average speed of an object is defined as :
(a) Total distance divided by total time
(b) Total time divided by total distance
(c) Distance divided by time at any instant
(d) None of the above
Answer:
(a) Total distance divided by total time
Question 4.
Which of the following statements is true regarding the time period of a simple pendulum?
(a) It varies with the mass of the bob.
(b) It is constant for a given length at a place.
(c) It increases with the length of the string.
(d) It decreases with the length of the string.
Answer:
(b) It is constant for a given length at a place.
Question 5.
In an hourglass, time is measured based on:
(a) The flow of water
(b) The flow of sand
(c) The movement of shadows
(d) The burning of candles
Answer:
(b) The flow of sand
Question 6.
What is the average speed of a car that travels 150 meters in 10 seconds?
(a) 15 m/s
(b) 30 m/s
(c) 60 m/s
(d) 150 m/s
Answer:
(a) 15 m/s
Question 7.
Which scientist first observed that the time taken for a pendulum to swing is consistent?
(a) Isaac Newton
(b) Christiaan Huygens
(c) Galileo Galilei
(d) Albert Einstein
Answer:
(c) Galileo Galilei
Case Study
I. Understanding the Simple Pendulum
A simple pendulum consists of a metallic ball, known as the bob, suspended from a rigid support by a long thread. When the bob is displaced from its mean position and released, it undergoes oscillatory motion. This motion is periodic, repeating its path after a fixed interval of time, which is defined as the time period of the pendulum.
Question 1.
What is the 'bob' of a simple pendulum?
(a) The thread from which the pendulum is suspended
(b) The rigid support holding the pendulum
(c) The metallic ball at the end of the thread
(d) The mean position of the pendulum
Answer:
(c) The metallic ball at the end of the thread
Explanation:
The bob is the small metallic ball that is suspended at the end of the thread in a simple pendulum.
Question 2.
The time taken by a pendulum to complete one full oscillation is called :
(a) Frequency
(b) Amplitude
(c) Time period
(d) Speed
Answer:
(c) Time period
Explanation: The time period is the fixed interval of time after which the pendulum repeats its path, completing one oscillation.
Question 3.
A simple pendulum consists of a metallic ball called the ............ suspended from a rigid support by a long thread.
Answer:
bob
Question 4.
The motion of a simple pendulum is ............ because it repeats its path after a fixed interval of time.
Answer:
periodic
Question 5.
The time period of a simple pendulum is the time taken by the bob to move from one extreme position to the other and back again. (True/False)
Answer:
True
Explanation: One complete oscillation is when the bob moves from its mean position to one extreme, then to the other extreme, and back to the mean position, or from one extreme to the other and back again. The time taken for this is called the time period.
II. Uniform and Non-Uniform Motion
In the context of motion, uniform motion occurs when an object travels equal distances in equal intervals of time, while non-uniform motion involves varying speeds. For example, a train moving at a constant speed between two stations illustrates uniform motion, where as a runner who speeds up or slows down during a marathon exemplifies non-uniform motion. Understanding these differences is fundamental in physics.
Question 1.
What type of motion is shown by an object that covers equal distances in equal intervals of time?
Answer:
Uniform motion.
Question 2.
Give one example of non-uniform motion mentioned in the paragraph.
Answer:
A runner who speeds up or slows down during a marathon.
Question 3.
Differentiate between uniform and non-uniform motion using examples from the paragraph.
Answer:
Uniform motion occurs when an object travels equal distances in equal intervals of time, like a train moving at constant speed between two stations. Non-uniform motion involves varying speeds, such as a runner who speeds up or slows down during a marathon.