i. Measurement is the comparison of an unknown quantity with some quantity.
ii. 1 km = m.
iii. Standard unit of length is .
iv. The length of curved line can be measured using a .
v. is the distance between two points or ends of an object.
vi. means the change in position of an object with time.
i. The choice of device used for the measurement depends on the type of measurement to be made.
ii. Our senses are reliable for accurate measurement.
iii. 1m = 100cm.
iv. 5km = 5000cm.
v. Motion of a child on a swing is periodic motion.
vi. Motion of a wheel of a cycle is random motion.
Ans. Measuring tape
Ans. Rectilinear or linear motion
Q5. Which unit of length is used to measure a large distance?
Q6. Write one example of circular motion.
Ans. Motion of hands of a clock
Q7. Write one example of rectilinear motion.
Ans. Motion of an apple falling from a tree
Q8. Write one example of periodic motion.
Ans. A bouncing ball
Q9. Name the type of motion in which a body moves along a curved path.
Ans. Circular or Rotational motion
Q10. Name the type of motion in which motion repeats after equal time interval.
Ans. Periodic motion
Ans. 1 km = 1000m
1340/1000 = 1.340 km
Ans. Each side = 5 x 10 = 50mm (All sides of square are equal)
Ans. The fixed quantity with which we compare an unknown quantity is called unit.
Q14. When object is said to be in rest?
Ans. If the position of an object does not change with time, it is said to be at rest.
Q15. What do you understand by ‘measurement’?
Ans. Measurement means the comparison of some unknown quantity with a known fixed quantity of same kind.
Q16. What is the common in between hand span, pace, angul and fist?
Ans. All of these are non-standard units of measurement that changes from person to person.
Q17. When object is said to be in motion?
Ans. When an object changes its position with time with respect to another object, it is said to be in motion.
Q18. Why is the hand span not considered as a reliable unit for measuring the length?
Ans. Hand span is not considered as a reliable unit for measuring the length because length of hand span varies from person to person.
Q19. What do you understand by standard unit of measurement?
Ans.The unit which is acceptable to the majority of people as a basic unit of measurement is called standard unit of measurement.