Free Work and Energy MCQs with Answers
748 Work and Energy MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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Read the Work and Energy notesFree MDCAT chapter notes with key terms748 questions · page 9 of 38
- A. 1/5 mv^2
- B. 1/2 mv^2
- C. mv^2
- D. 2/5 mv^2
Explanation: Explanation: The correct formula for the rotational kinetic energy of a solid sphere is 2/5 mv^2, where m is the mass of the sphere and v…
Correct answer: 2/5 mv^2162. If E is the K.E of body moving in circle of radius r then the centripetal force may be written as
- A. A
- B. B
- C. C
- D. D
Explanation: The explanation is given below: If 'E' represents the kinetic energy (K.E) of a body moving in a circle with a radius 'r,' the centripetal…
Correct answer: D- A. √gh
- B. √4/3gh
- C. √3/4gh
- D. √5/6gh
Explanation: Here is the explanation of the correct option
Correct answer: √4/3gh- A. 2.8 J
- B. 3.2 J
- C. 3.8 J
- D. 4.4 J
Explanation: The initial momentum of the body is given as 10 kg m/s. Using the definition of momentum, we can find the initial velocity of the body…
Correct answer: 4.4 J- A. 1:2
- B. 1:4
- C. 4:1
- D. 1:1
Explanation: Since K.E is inversely propotional to the mass the ratio of the masses will be inverted and would become 1:4.
Correct answer: 1:4- A. ½
- B. ¼
- C. ⅛
- D. ⅙
Explanation: KE=½ mv2KE= ½ m(½v)2KE=⅛ mv2As it can be seen, the fraction reduces from 1/2 to 1/8 which means the Kinetic Energy decreased by 4 times or…
Correct answer: ¼- A. mgh
- B. Zero
- C. 1/2 mv2
- D. 2mgh
Explanation: Ooption B is corrrect.The kinetic energy (KE) of a stone is equal to zero at its maximum height.
Correct answer: Zero- A. A. A rolling ball (kinetic) and a compressed spring (potential)
- B. B. A stationary car (kinetic) and a falling rock (potential)
- C. C. A flowing river (kinetic) and a charged battery (potential)
- D. D. A swinging pendulum at its highest point (kinetic) and a moving car (potential)
Explanation: The correct answer is Option A. Kinetic energy is the energy of motion, exemplified by a rolling ball.
Correct answer: A. A rolling ball (kinetic) and a compressed spring (potential)- A. Potential Energy
- B. Thermal Energy
- C. Kinetic Energy
- D. Chemical Energy
Explanation: This is correct because kinetic energy is directly linked to motion and given by (1/2)mv².
Correct answer: Kinetic Energy- A. Same
- B. 2 times
- C. 4 times
- D. 16 times
Explanation: This is correct because KE ∝ v², so if KE becomes 4 times, then v² becomes 4 ⇒ v = 2v.
Correct answer: 2 times- A. 3 J
- B. 6 J
- C. 9 J
- D. 18 J
Explanation: This is correct because KE = ½ × 2 × (3²) = ½ × 2 × 9 = 9 J.
Correct answer: 18 J- A. Negative
- B. Positive
- C. Zero
- D. All of these
Explanation: Option C is correct.Yes, the absolute gravitational potential energy of an object at infinite height with respect to Earth is taken as…
Correct answer: Zero- A. 5 J
- B. 320 J
- C. 25 J
- D. All of these
Explanation: Option A is correct.Given that:Height of the man: 2 mHeight of the tower: 30 mMass of the object: 1 kgDistance raised: 0.5 mAcceleration…
Correct answer: 5 J- A. Heat energy to K.E
- B. Chemical energy to elastic P.E
- C. Elastic P.E to K.E
- D. K.E to elastic P.E
Explanation: When an arrow is thrown from its bow, the elastic P.E. of the bow is transferred to arrow as its K.E.
Correct answer: Elastic P.E to K.E- A. Work done inside that field is independent of the path followed
- B. Work done in closed path inside that field is zero
- C. Both A and B
- D. Work done is always negative
Explanation: i. The field in which work done on a body does not depend on the path followed by the body is called conservative field.ii.
Correct answer: Both A and B- A. Only potential energy
- B. Only kinetic energy
- C. Half potential and half kinetic energy
- D. More kinetic and less potential energy
Explanation: P.E = mghP.E = mgh/2 [h' = h/2]P.E' = P.E/2So at h/2. body has half P.E and half K.E.
Correct answer: Half potential and half kinetic energy- A. I only
- B. III only
- C. II and III
- D. I and II
Explanation: The work done by the gravitational force to move a body from the surface of Earth to infinity is termed the 'absolute potential energy' of…
Correct answer: III only- A. Vary at different paths.
- B. Be greater for the longer path.
- C. Be same and equal to its kinetic energy.
- D. Be same and equal to its potential energy.
Explanation: The correct answer is that the work done in moving the object in a gravitational field is the same regardless of the path taken, as long…
Correct answer: Be same and equal to its potential energy.- A. A: The packet moves without any external force.
- B. B: The packet accelerates due to gravitational force.
- C. C: The packet remains stationary unless pushed.
- D. D: The gravitational component along the plane causes the packet to slide down.
Explanation: The correct answer is Option D: The gravitational component along the plane causes the packet to slide down.
Correct answer: D: The gravitational component along the plane causes the packet to slide down.- A. 7.2 kJ
- B. 720 J
- C. 120 J
- D. 72000 J
Explanation: P = 60W t = 2 minutes =2×60 seconds =120 seconds E= P×twhere ( E ) is the energy in joules (J), ( P ) is the power in watts (W), and ( t )…
Correct answer: 7.2 kJ