MCQs / Physics / Deformation of Solids

Deformation of Solids MCQs — Physics (page 2)

110 multiple-choice questions on Deformation of Solids from Physics, each with the correct answer and, where available, a teacher's explanation. Read through them to revise the chapter, then practise the same questions one by one to test yourself.

26. Why is the work done for a Hooke's-law spring 12Fe and not Fe?

  1. Fe is the momentum
  2. the spring only moves half the distance
  3. half the energy is lost as heat
  4. the force rises from zero to F, so the average force is F2

Answer: D) the force rises from zero to F, so the average force is F2

Explanation: Work = average force × extension. SLO P-11-B-27 · Application

Discuss this question

27. A spring's force rises linearly from 10 N at extension 0.02 m to 30 N at 0.06 m. The work done over this range is:

  1. 1.6 J
  2. 0.8 J
  3. 0.4 J
  4. 1.2 J

Answer: B) 0.8 J

Explanation: Area of the trapezium = 12(10 + 30)(0.06 - 0.02) = 0.8 J. SLO P-11-B-27 · Application

Discuss this question

28. A spring of spring constant 50 N/m is stretched by 0.3 m (within the limit of proportionality). The elastic potential energy stored is:

  1. 4.5 J
  2. 2.25 J
  3. 1.12 J
  4. 7.5 J

Answer: B) 2.25 J

Explanation: Ep = 12kx^2 = 12(50)(0.3)^2 = 2.25 J. SLO P-11-B-28 · Application

Discuss this question

29. For a non-linear force–extension graph, the work done is found by:

  1. dividing the force by extension
  2. multiplying the final force by the extension
  3. estimating the area under the curve (e.g. counting squares)
  4. using 12Fe always

Answer: C) estimating the area under the curve (e.g. counting squares)

Explanation: The triangle formula only works for a straight line. SLO P-11-B-27 · Application

Discuss this question

30. The basic repeating unit of a crystal lattice is called the:

  1. molecule chain
  2. grain boundary
  3. monomer
  4. unit cell

Answer: D) unit cell

Explanation: The lattice is built by repeating the unit cell. SLO P-11-B-22 · Understanding

Discuss this question

31. Two springs are stretched by the same force. The one with the larger extension stores:

  1. no energy
  2. the same energy
  3. less energy
  4. more energy

Answer: D) more energy

Explanation: W = 12Fe. SLO P-11-B-27 · Application

Discuss this question

32. Stress is defined as:

  1. stress/strain
  2. force per unit cross-sectional area
  3. extension per unit length
  4. force × extension

Answer: B) force per unit cross-sectional area

Explanation: sigma = F/A, unit pascal. SLO P-11-B-24 · Application

Discuss this question

33. In the experiment, the load is increased:

  1. until the wire breaks first
  2. in equal steps, recording the extension each time
  3. all at once
  4. randomly

Answer: B) in equal steps, recording the extension each time

Explanation: This gives a series of points for a graph. SLO P-11-B-25 · Understanding

Discuss this question

34. An amorphous (glassy) solid, when heated:

  1. turns directly into gas
  2. never softens
  3. softens gradually over a range of temperatures
  4. melts sharply at one temperature

Answer: C) softens gradually over a range of temperatures

Explanation: Bonds have different strengths. SLO P-11-B-22 · Understanding

Discuss this question

35. A toy gun's spring (k = 200 N/m) is compressed 0.1 m and launches a 50 g ball. Ignoring losses, the ball's speed is:

  1. 8.94 m/s
  2. 12.6 m/s
  3. 6.32 m/s
  4. 3.16 m/s

Answer: C) 6.32 m/s

Explanation: 12kx^2 = 12mv^2 Rightarrow v = x km = 6.32 m/s. SLO P-11-B-28 · Application

Discuss this question

36. Polymers are made of:

  1. ions in a regular array
  2. free electrons only
  3. long chain molecules built from repeating units (monomers)
  4. single atoms in a cubic lattice

Answer: C) long chain molecules built from repeating units (monomers)

Explanation: e.g. polythene: repeated CH2 units. SLO P-11-B-22 · Understanding

Discuss this question

37. A ductile material such as copper:

  1. has no elastic region
  2. can be drawn into wires (shows large plastic deformation)
  3. is amorphous
  4. breaks without deforming

Answer: B) can be drawn into wires (shows large plastic deformation)

Explanation: Ductile = can be drawn out. SLO P-11-B-26 · Understanding

Discuss this question

38. A wire of length 3 m and cross-section 5 10^-6 m^2 extends by 3 mm under 1000 N. The Young modulus is:

  1. 2 10^11 Pa
  2. 4 10^11 Pa
  3. 2 10^10 Pa
  4. 2 10^12 Pa

Answer: A) 2 10^11 Pa

Explanation: Y = F/Ae/l = FlAe = 2 10^11 Pa. SLO P-11-B-24 · Application

Discuss this question

39. A spring of constant 400 N/m stores 2 J of elastic energy. Its extension is:

  1. 0.01 m
  2. 0.2 m
  3. 0.1 m
  4. 0.05 m

Answer: C) 0.1 m

Explanation: x = 2Ek = 2(2)400 = 0.1 m. SLO P-11-B-28 · Application

Discuss this question

40. A spring obeying Hooke's law extends 0.4 cm under a final force of 250 N. The work done in stretching it is:

  1. 0.25 J
  2. 1 J
  3. 50 J
  4. 0.5 J

Answer: D) 0.5 J

Explanation: Work = area of the triangle = 12Fe = 12(250)(0.004) = 0.5 J. SLO P-11-B-27 · Application

Discuss this question

41. A graph of force (N) against extension (m) has area 0.5 N m. The energy stored is:

  1. 5 J
  2. 50 J
  3. 0.5 J
  4. 0.05 J

Answer: C) 0.5 J

Explanation: N m = J. SLO P-11-B-27 · Application

Discuss this question

42. Ep = 12Fx and Ep = 12kx^2 are equivalent because:

  1. F = kx^2
  2. F = kx
  3. k = Fx
  4. F = 12kx

Answer: B) F = kx

Explanation: Substitute Hooke's law. SLO P-11-B-28 · Application

Discuss this question

43. A spring of spring constant 800 N/m is stretched by 0.05 m (within the limit of proportionality). The elastic potential energy stored is:

  1. 20 J
  2. 2 J
  3. 1 J
  4. 0.5 J

Answer: C) 1 J

Explanation: Ep = 12kx^2 = 12(800)(0.05)^2 = 1 J. SLO P-11-B-28 · Application

Discuss this question

44. When a solid is compressed, the atoms:

  1. stop vibrating
  2. move further apart
  3. are destroyed
  4. are pushed closer and repel each other

Answer: D) are pushed closer and repel each other

Explanation: Repulsive forces resist compression. SLO P-11-B-23 · Understanding

Discuss this question

45. In one-dimensional deformation, the change in the length of a wire is called the:

  1. stress
  2. strain energy
  3. extension
  4. Young modulus

Answer: C) extension

Explanation: Extension e = l - l0. SLO P-11-B-23 · Understanding

Discuss this question

46. Which of these is a crystalline solid?

  1. rubber
  2. glass
  3. sodium chloride (common salt)
  4. polythene

Answer: C) sodium chloride (common salt)

Explanation: Salt forms cubic crystals. SLO P-11-B-22 · Understanding

Discuss this question

47. A force that squashes a pillar produces:

  1. no deformation
  2. torsion
  3. tensile deformation
  4. compressive deformation

Answer: D) compressive deformation

Explanation: Compression decreases the length. SLO P-11-B-23 · Understanding

Discuss this question

48. A compression spring in a car's suspension:

  1. gets longer under load
  2. breaks at once
  3. gets shorter under load
  4. keeps its length

Answer: C) gets shorter under load

Explanation: It is compressed. SLO P-11-B-23 · Understanding

Discuss this question

49. A catapult converts elastic potential energy into:

  1. kinetic energy of the stone
  2. chemical energy
  3. nuclear energy
  4. only heat

Answer: A) kinetic energy of the stone

Explanation: Energy conservation. SLO P-11-B-28 · Application

Discuss this question

50. A spring with k = 200 N/m is stretched 0.1 m. The area under its force–extension graph is:

  1. 10 J
  2. 20 J
  3. 1 J
  4. 2 J

Answer: C) 1 J

Explanation: 12(200)(0.1)^2 = 1 J. SLO P-11-B-27 · Application

Discuss this question

Previous Page 2 of 5 Next

Practise Deformation of Solids MCQs

More Physics chapters