MCQ | NCERT Class 9 Science | Chapter 5: Measurement of Length and Motion
Q1. What is measurement?
(a) Comparing an unknown quantity with a known standard quantity
(b) Guessing the size of an object
(c) Observing an object without comparing it
(d) Counting only the number of objects
Answer: (a) Comparing an unknown quantity with a known standard quantity
Q2. Which of the following is the standard SI unit of length?
(a) Centimetre
(b) Metre
(c) Kilometre
(d) Millimetre
Answer: (b) Metre
Q3. Which instrument is commonly used to measure the length of an object?
(a) Thermometer
(b) Ruler
(c) Compass
(d) Balance
Answer: (b) Ruler
Q4. Which unit is suitable for measuring the length of a pencil?
(a) Kilometre
(b) Metre
(c) Centimetre
(d) Litre
Answer: (c) Centimetre
Q5. Which unit is more suitable for measuring the distance between two cities?
(a) Millimetre
(b) Centimetre
(c) Metre
(d) Kilometre
Answer: (d) Kilometre
Q6. One metre is equal to
(a) 10 centimetres
(b) 100 centimetres
(c) 1000 centimetres
(d) 10 kilometres
Answer: (b) 100 centimetres
Q7. One centimetre is equal to
(a) 10 millimetres
(b) 100 millimetres
(c) 1000 millimetres
(d) 1 millimetre
Answer: (a) 10 millimetres
Q8. Which of the following is the smallest unit of length among these?
(a) Kilometre
(b) Metre
(c) Centimetre
(d) Millimetre
Answer: (d) Millimetre
Q9. While measuring the length of an object with a ruler, the object should preferably be placed
(a) away from the ruler
(b) along the scale of the ruler
(c) above the ruler without touching it
(d) at any random angle
Answer: (b) along the scale of the ruler
Q10. What should be done if the zero mark of a ruler is damaged?
(a) Stop measuring completely
(b) Start from another clear mark and subtract the initial reading from the final reading
(c) Guess the length
(d) Use the zero mark only
Answer: (b) Start from another clear mark and subtract the initial reading from the final reading
Q11. If one end of an object is at the 2 cm mark and the other end is at the 8 cm mark, its length is
(a) 6 cm
(b) 8 cm
(c) 10 cm
(d) 4 cm
Answer: (a) 6 cm
Q12. Which of the following is important for obtaining an accurate measurement?
(a) Reading the scale from an angle
(b) Keeping the eye directly above the reading
(c) Guessing the reading
(d) Keeping the ruler tilted randomly
Answer: (b) Keeping the eye directly above the reading
Q13. What is motion?
(a) Change in position of an object with time
(b) Change in colour of an object
(c) Increase in mass of an object
(d) Change in temperature only
Answer: (a) Change in position of an object with time
Q14. An object is said to be at rest when
(a) its position changes continuously
(b) its position does not change with respect to a reference point
(c) it is always moving slowly
(d) it changes its shape
Answer: (b) its position does not change with respect to a reference point
Q15. Which of the following is an example of a moving object?
(a) A parked car
(b) A moving bicycle
(c) A book lying on a table
(d) A stationary tree
Answer: (b) A moving bicycle
Q16. What is a reference point?
(a) A point with respect to which the position or motion of an object is described
(b) A point that always moves
(c) A measuring instrument
(d) A unit of length
Answer: (a) A point with respect to which the position or motion of an object is described
Q17. Why is a reference point important when describing motion?
(a) Motion is described by comparing the position of an object with a reference point
(b) It changes the mass of an object
(c) It measures temperature
(d) It gives the colour of an object
Answer: (a) Motion is described by comparing the position of an object with a reference point
Q18. Which of the following can be used as a reference point?
(a) A tree
(b) A fixed building
(c) A pole
(d) All of these
Answer: (d) All of these
Q19. A person sitting inside a moving bus is at rest with respect to
(a) a person sitting beside them in the same bus
(b) a person standing on the roadside
(c) a tree beside the road
(d) a building outside the bus
Answer: (a) a person sitting beside them in the same bus
Q20. A person sitting in a moving bus is in motion with respect to
(a) another passenger sitting beside them
(b) the seat next to them
(c) a tree beside the road
(d) another stationary object inside the bus
Answer: (c) a tree beside the road
Q21. Which type of motion does the Earth show while revolving around the Sun?
(a) Circular or nearly circular motion
(b) Only straight-line motion
(c) No motion
(d) Random motion
Answer: (a) Circular or nearly circular motion
Q22. The motion of a swing moving to and fro is called
(a) periodic motion
(b) straight-line motion
(c) random motion
(d) stationary motion
Answer: (a) periodic motion
Q23. Which of the following is an example of rotational motion?
(a) A spinning top
(b) A person walking straight
(c) A car moving on a straight road
(d) A ball rolling in a straight line
Answer: (a) A spinning top
Q24. Which of the following shows straight-line motion?
(a) A car moving along a straight road
(b) The hands of a clock
(c) A spinning wheel
(d) A rotating fan
Answer: (a) A car moving along a straight road
Q25. Which statement correctly describes motion?
(a) An object can be considered in motion or at rest depending on the reference point
(b) Every object is always in motion
(c) Every object is always at rest
(d) Motion does not depend on position
Answer: (a) An object can be considered in motion or at rest depending on the reference point
