DensityCopy

1. Which of the following does not affect the density of a substance?

A) The material’s atomic arrangement
B) Temperature
C) Mass
D) Shape of the container

2. If the density of oil is 0.8 g/cm³, and a metal block of volume 10 cm³ displaces oil of mass 6 g, what is the density of the block?

A) 0.6 g/cm³
B) 1.2 g/cm³
C) 0.8 g/cm³
D) 0.75 g/cm³

3. The most precise instrument to measure volume of an irregular solid is:

A) Beaker
B) Measuring cylinder
C) Overflow can
D) Ruler

4. An object has mass 600 g and volume 400 cm³. It is completely immersed in water. What force does it experience due to upthrust?

A) 4 N
B) 3.2 N
C) 2.5 N
D) 1.8 N

5. A student uses a balance and a ruler to find the density of a cube. Which combination will reduce percentage error the most?

A) Small mass, large edge length
B) Large mass, large edge length
C) Small mass, small edge length
D) Large mass, small edge length

6. A solid metal sphere and a hollow metal sphere of same mass but different volumes are dropped into water. Which of the following must be true?

A) Both have same density
B) Hollow one floats
C) Solid one displaces more water
D) Hollow one sinks faster

7. Which of the following has the unit kg/m³ but is not a density?

A) Pressure gradient
B) Mass per unit volume
C) Weight per unit height
D) Force per unit acceleration

8. A rectangular block measures 3.0 cm × 2.0 cm × 1.0 cm and has a mass of 36 g. Its density is:

A) 3 g/cm³
B) 6 g/cm³
C) 12 g/cm³
D) 9 g/cm³

9. Density is defined as:

A) Weight ÷ volume
B) Mass × volume
C) Volume ÷ mass
D) Mass ÷ volume

10. Which physical property remains constant for a pure substance regardless of its sample size?

A) Mass
B) Volume
C) Density
D) Weight

11. Which instrument is best for measuring small volume changes due to immersion?

A) Burette
B) Pipette
C) Eureka can
D) Vernier caliper

12. Which of the following SI unit combinations correctly expresses density?

A) N/m³
B) kg/m²
C) kg/m³
D) J/m³

13. An object floats in water but sinks in alcohol. Which statement is most accurate?

A) Object’s density is more than water
B) Water is denser than alcohol
C) Alcohol is more viscous
D) Alcohol has higher surface tension

14. A sphere of radius r is made of material X. If radius is doubled but same material is used, density:

A) Doubles
B) Halves
C) Stays same
D) Quadruples

15. What happens to the density of water when it is heated from 0°C to 4°C?

A) Increases
B) Decreases
C) Remains constant
D) Oscillates

16. Density is a scalar because:

A) It has no direction
B) It depends on volume
C) It is derived from scalar quantities
D) Both A and C

17. Two substances have same volume but different densities. Which one has greater mass?

A) The denser one
B) The lighter one
C) Both have equal mass
D) Cannot say

18. For accurate density measurement of irregular object, we need:

A) Precise stopwatch
B) Digital thermometer
C) Micrometer screw gauge
D) Eureka can and digital balance

19. When a stone is placed in water, the volume reading increases. This change is:

A) The stone’s density
B) The stone’s mass
C) The stone’s volume
D) The buoyant force

20. Which has highest density?

A) Lead
B) Iron
C) Mercury
D) Osmium

21. What happens to density of air as altitude increases?

A) Increases
B) Decreases
C) Remains constant
D) First increases, then decreases

22. An object with lower density than water will:

A) Sink
B) Float
C) Remain suspended
D) Evaporate

23. A 2 kg block occupies 250 cm³. What’s its density in kg/m³?

A) 8000
B) 7500
C) 6000
D) 7200

24. Two liquids do not mix and form layers. The denser one:

A) Floats
B) Mixes partially
C) Sinks
D) Forms emulsion

25. A gas in a rigid container is heated. Its mass stays same, but density:

A) Increases
B) Decreases
C) Stays same
D) Triples

26. Which principle is used in a Eureka can?

A) Archimedes’ Principle
B) Pascal’s Law
C) Boyle’s Law
D) Newton’s First Law

27. If a body’s mass triples and volume doubles, new density is:

A) 1.5× original
B) 3× original
C) 2× original
D) 0.67× original

28. Which is the most accurate method to measure density of a powder?

A) Measuring cylinder method
B) Displacement method
C) Pycnometer method
D) Using a burette

29. A 200 cm³ object has 4.0 × 10⁻² kg mass. What is its density in g/cm³?

A) 0.2
B) 2.0
C) 0.5
D) 1.0

30. The density of a floating object is 0.6 g/cm³. What percentage of it is submerged?

A) 40%
B) 60%
C) 100%
D) 30%

31. Mass = 50 g, Volume = 40 cm³. What is the error in density if volume error is ±2 cm³?

A) ±0.025 g/cm³
B) ±0.5 g/cm³
C) ±2 g/cm³
D) ±1.25 g/cm³

32. A hollow metal object has apparent mass 150 g in air, 100 g in water. Volume is:

A) 100 cm³
B) 50 cm³
C) 25 cm³
D) 150 cm³

33. If the density of water is 1 g/cm³, what is the minimum density a cube must have to just sink?

A) 0.8 g/cm³
B) 1.0 g/cm³
C) 1.2 g/cm³
D) 0.5 g/cm³

34. Which graph represents a constant density object?

A) Curved mass vs. volume
B) Straight line through origin for mass vs. volume
C) Flat mass vs. volume
D) Volume increasing exponentially with mass

35. Which error will lead to highest uncertainty in density measurement?

A) Error in length of cube
B) Error in time measurement
C) Error in stopwatch calibration
D) Error in stopwatch resolution

MARKING KEY + EXPLANATIONS

Written and Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change O Level And IGCSE Physics Full Scale Course