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Work, Energy, and Power — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysicsWork, Energy, and Power4 Marks
Question
Read the case study given below and answer any four subparts:
Potential energy is the energy stored within an object, due to the object's position, arrangement or state. Potential energy is one of the two main forms of energy, along with kinetic energy. Potential energy depends on the force acting on the two objects.

  1. A body is falling freely under the action of gravity alone in vacuum. Which of the following quantities remain constant during the fall?
    1. kinetic energy
    2. potential energy
    3. mechanical energy
    4. none of these
  2. Work done by a conservative force is positive, if
    1. potential energy decreases
    2. potential energy increases
    3. kinetic energy decreases
    4. kinetic energy increases
  3. When does the potential energy of a spring increases?
    1. only when spring is stretched
    2. only when spring is compressed 
    3. both a and b
    4. none of these
  4. Dimension of k/m is, here k is force constant
    1. T2
    2. T-2
    3. T1
    4. T-1
  5. A vehicle of mass 5000kg climbs up a hill of 10 m. The potential energy gained by it
    1. 5J
    2. 500J
    3. 5 × 104J
    4. 5 × 105J
✓

Answer

  1. (c) mechanical energy
  2. (a) potential energy decreases
  3. (c) both a and b
  4. (b) T-2
  5. (d) 5 × 105J

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