Class 6 Science Chapter 7 Case Based Questions - Motion and Measurement of Distances

Case 1: The Wheel's Invention

In ancient times, wheels were not a common means of transportation. People relied on animals and boats. The invention of the wheel changed the course of history.

Q1: Why was the invention of the wheel significant for transportation?
Ans: The invention of the wheel was significant for transportation because it revolutionized the way people and goods could be moved, making transportation more efficient and less physically demanding.

Q2: Explain the evolution of transportation methods before the wheel's invention.
Ans: Before the invention of the wheel, people relied on animals like donkeys, horses, and oxen, as well as boats for transportation. These methods were slower and limited in their capacity to transport goods and people efficiently.

Q3: Describe how the invention of the wheel led to the development of different modes of transport.
Ans: The invention of the wheel led to the development of various modes of transport, including bullock carts, chariots, bicycles, mopeds, cars, trains, ships, airplanes, and even spacecraft.

Q4: What was the primary means of transportation before the invention of the wheel?
(a) Horses
(b) Boats
(c) Bicycles
(d) Airplanes
Ans: (b)

Q5: How did the invention of the wheel impact transportation?
(a) It had no impact.
(b) It revolutionized transportation.
(c) It led to the development of space travel.
(d) It caused pollution.
Ans: (b)

Case 2: Standard Units of Measurement

Ancient civilizations used various body parts for measurement. Later, standardized systems like the metric system were introduced.

Q6: Why was it necessary to establish standard units of measurement?
Ans: Standard units of measurement were necessary to ensure consistency and uniformity in measuring length and distance.

Q7: Explain the concept of the cubit and its use in ancient Egypt.
Ans: The cubit was a unit of measurement used by the Egyptians, measured from the point where the elbow bends to the tip of the middle finger. It was equal to 18 inches.

Q8: Describe the transition from non-standard units of measurement to the metric system.
Ans: The transition from non-standard units to the metric system helped achieve uniformity in measurement worldwide.

Q9: What was the cubit used for in ancient Egypt?
(a) Measuring time
(b) Measuring length
(c) Measuring weight
(d) Measuring temperature
Ans: (b)

Q10: Which system of measurement is widely used across the world today?
(a) Imperial system
(b) Metric system
(c) Ancient system
(d) Customary system
Ans: (b)

Case 3: Rest and Motion

Understanding the concepts of rest and motion is crucial to describe the state of objects around us.

Q11: Define rest and motion and provide examples of each.
Ans: Rest refers to a state in which an object remains in one position for a long time, while motion is a change in position with respect to time.

Q12: Explain how an object can be at rest with respect to one observer but in motion with respect to another.
Ans: An object can be at rest with respect to one observer (e.g., a passenger on a train) but in motion with respect to another observer (e.g., a person on the ground).

Q13: Give examples of objects that exhibit both rest and motion simultaneously.
Ans: Examples of objects exhibiting both rest and motion simultaneously include trees, buildings, and mountains, which are relatively at rest with respect to each other.

Q14: When does an object exhibit rest?
(a) When it is moving at a constant speed.
(b) When it changes its position with respect to time.
(c) When it remains in one position for a long time.
(d) When it accelerates.
Ans: (c)

Q15: Which of the following is an example of an object in motion?
(a) A chair
(b) A person standing still
(c) A car moving on a road
(d) A tree
Ans: (c)

Case 4: Types of Motion

There are different types of motion, including rectilinear, circular, and periodic motion, each with its unique characteristics.

Q16: Define and provide examples of rectilinear, circular, and periodic motion.
Ans: Rectilinear motion is motion in a straight line, circular motion involves moving at a fixed distance from a fixed point, and periodic motion repeats at regular intervals.

Q17: Explain how a car moving on a road can exhibit both rectilinear and circular motion.
Ans: A car moving on a road exhibits both rectilinear motion (along the road) and circular motion (the wheels rotating).

Q18: Describe why periodic motion is essential in various aspects of our daily lives.
Ans: Periodic motion is essential in various aspects of our daily lives, such as pendulum clocks, musical instruments, and even in the functioning of engines.

Q19: What type of motion does a spinning top exhibit?
(a) Rectilinear motion
(b) Circular motion
(c) Periodic motion
(d) Rest
Ans: (c)

Q20: Which type of motion repeats itself at regular intervals of time?
(a) Rectilinear motion
(b) Circular motion
(c) Periodic motion
(d) Random motion
Ans: (c)

Case 5: Importance of Knowing Distance

Knowing the distance between places is vital for choosing the right mode of transportation.

Q21: Explain why it is important to know the distance between places before planning a journey.
Ans: It is important to know the distance between places before planning a journey to choose the most suitable mode of transportation and estimate travel time accurately.

Q22: Discuss the concept of estimation and its role in planning a journey.
Ans: Estimation involves guessing the dimensions of an object without actual measuring and is essential for planning journeys.

Q23 Explore the types of scales used by different professionals to measure length.
Ans: Different professionals use various scales for measurement, such as iron/steel metre scales by cloth merchants, plastic metre tape by tailors, and both plastic metre tapes and iron metre scales by carpenters.

Q24: Why is it essential to estimate distances when planning a journey?
(a) To impress others with knowledge
(b) To choose the most suitable mode of transportation
(c) To increase travel time
(d) To avoid traffic jams
Ans: (b)

Q25: What kind of scale is typically used by carpenters to measure length?
(a) Plastic metre tape
(b) Iron/steel metre scale
(c) Kilometer scale
(d) Ancient measuring stick
Ans: (b)