Class 6 Science Chapter 7 Question Answers - Motion and Measurement of Distances

Q1: The known fixed quantity of measurement is called __________.

Ans: Unit. 

A unit is a standard quantity used for measurement, such as meter for length or kilogram for weight.

Q2: What do you mean by the term ‘measurement’?

Ans: The comparison of an unknown quantity with some known quantity is called measurement.

Measurement involves comparing an unknown quantity with a standard unit to determine its size, length, volume, etc.

Q3: What is the full form of SI units?

Ans: International System of Units. 

SI units are the globally accepted standard units of measurement used in science and daily life.

Q4: What is the SI unit of length?

Ans: Metre. 

The metre is the SI unit of length, used to measure distances and lengths.

Q5: Yard is a measure of distance between:

a) Two hands
b) The hand and the feet
c) Between the hand and the elbow
d) End of the arm and the chin

Ans: d 

Yard is traditionally measured from the end of the arm to the chin.

Q6: In ancient India small length measurements used were angul and mutthi. (TRUE/FALSE)

Ans: True. 

Angul and mutthi were traditional units of measurement for small lengths in ancient India.

Q8: What is motion?

Ans: Motion refers to the movement of an object from one place to another over time.

Q9: 1 metre is equal to __cm.

Ans: 100. 

One metre is equivalent to 100 centimetres.

Q10: We can measure the length of a curved line directly by using a metre scale. (TRUE/FALSE)

Ans: False.

A metre scale is straight and cannot measure the length of a curved line directly.

Q11: What are the different types of motion?

Ans: Rectilinear motion, circular motion, rotational motion and periodic motion. These are the four primary types of motion based on the path and pattern of movement.

Q12: When objects move along a straight line such motion is called ______ motion.

Ans: Rectilinear motion. 

Rectilinear motion occurs when objects travel in a straight path.

Q13: One centimetre is equal to _______millimetre.

Ans: 10.

One centimetre is equivalent to ten millimetres.

Q14: When an object moves in a circular path, such motion is called _________.

Ans: Circular motion. 

Circular motion is the movement of an object along the circumference of a circle.

Q15: Give one example of periodic motion.

Ans: The motion of a pendulum is a periodic motion. A pendulum swings back and forth in a regular, repeating pattern, demonstrating periodic motion.

Q16: One kilometre is equal to __________ metre.

Ans: 1000. 

One kilometre is equivalent to one thousand meters.

Q18: 2 km is equal to _________m and ________cm.

Ans: 2000 m and 200000 cm. 

Two kilometres are equal to two thousand meters and two hundred thousand centimetres.

Q19: In periodic motion, an object repeats its motion. (TRUE/FALSE)

Ans: True. 

Periodic motion involves an object repeating its movement at regular intervals.

Q20: 8 km is equal to ___m.

Ans: 8000. 

Eight kilometres are equivalent to eight thousand meters.

Q21: The length of a rope is 5m. Express it in cm.

Ans: 5 m = 500 cm. 

Five meters are equal to five hundred centimetres.

Q22: A ball is rolling on the ground, rotating as well as moving forward on the ground. Therefore, it undergoes _____________ and ___________ motion.

Ans: Rectilinear and rotational. 

The ball moves in a straight line (rectilinear) and rotates on its axis (rotational).

Q23: What were the early modes of transport before the invention of the wheel?

Ans: Early modes of transport included walking on foot and using animals to carry goods.

Q24: What did people use to measure lengths before standard scales were made?

Ans: People used their body parts such as the length of a foot, the width of a finger, and the distance of a step.

Q25: What is the importance of the correct position of the eye in taking measurements?

Ans: The correct position of the eye ensures an accurate reading of the measurement scale, avoiding parallax errors.

Q26: How can you measure a length if the zero mark on a scale is broken?

Ans: Use any other full mark on the scale, measure from that mark, and then subtract its reading from the reading at the other end.

Q27: How did ancient people use the 'cubit' for measurement?

Ans: The cubit was the length from the elbow to the fingertips and was used as a unit of length.

Q28: What is the SI unit for large distances?

Ans: Kilometre (km). 

Kilometre is used for measuring large distances, with 1 km equal to 1000 meters.

Q29: Why are standard units of measurement important?

Ans: Standard units of measurement provide uniformity and consistency, allowing accurate and comparable measurements.

Q30: What type of motion does a sewing machine needle exhibit?

Ans: Periodic motion.

The needle of a sewing machine moves up and down continuously, repeating its motion.