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 31 of 38
- A. 1 J
- B. 10 J
- C. 0 J
- D. 0.1 J
Explanation: The work done in terms of height to give an object 1 Joule (J) of potential energy is 1 J. So, the correct answer is: 1 J
Correct answer: 1 J- A. 316 J
- B. 216 J
- C. 392 J
- D. 416 J
Explanation: Bpth GPE and KE have to be calculated.(m x g x h)+(0.5 x m x v^2) = 216J
Correct answer: 216 J- A. 7.2 J
- B. 3.6J
- C. 120 J
- D. 1200 J
Explanation: B is correct.Data:Mass of 2 m chain = 4kgMass of 0.6m chain = 1.2 kgForce = Mass x Accelaration due to gravityF= 1.2 x 10F= 12NWork =…
Correct answer: 3.6J- A. 100J
- B. 1.875J
- C. 18.75J
- D. 187.5J
Explanation: To find the work done to raise the bird's own center of mass to the branch, we need to use the formula: Work = force x distance x…
Correct answer: 100J605. A cubic vessel of height 1 m is full of water. The minimum work done in taking the water out is:
- A. 5000 J
- B. 10000 J
- C. 5 J
- D. 10 J
Explanation: Total water volume = 1m × 1m × 1m = 1m3 mass = 1m3 × 1000 kgm-3 = 1000 kg .
Correct answer: 5000 J- A. 0.33 litre of petrol
- B. 1 litre of petrol
- C. 0.5 litre of petrol
- D. 2 litre of petrol
Explanation: The food we eat in one day has about the same energy as 0.33 litre of petrol.
Correct answer: 0.33 litre of petrol- A. Kinetic energy
- B. Potential energy
- C. Power
- D. Work done
Explanation: The product of force and velocity is called power.
Correct answer: Power608. lhp is equal to
- A. 476 watts
- B. 647 waits
- C. 746 watts
- D. 467 watts
Explanation: One mechanical horsepower of 550 foot-pounds per second is equivalent to 745.7 watts.
Correct answer: 746 watts- A. Kinetic energy
- B. Potential energy
- C. Power
- D. Work done
Explanation: The product of force and velocity is power.
Correct answer: Power- A. 1500 w
- B. 742 w
- C. 148 w
- D. 1492 w
Explanation: A fully loaded 2 HP motor at 100% efficiency consumes 2 x 0.746 = 1.492 kW per hour.
Correct answer: 1492 w- A. Current
- B. Volt
- C. Resistance
- D. Power
Explanation: Volt multiplied by Ampere equals Watt, which is the unit of power.
Correct answer: Power- A. Force and displacement
- B. Force and velocity
- C. Force and time
- D. Work and time
Explanation: Power (P) is calculated as the dot product of force (F) and velocity (v), which represents the rate at which work is done.
Correct answer: Force and velocity- A. KE decreases
- B. PE increases
- C. Both (A) and (B)
- D. None of these
Explanation: If the work done by gravity is negative, it means that the gravitational force is acting in the direction opposite to the direction of…
Correct answer: Both (A) and (B)- A. 475 J
- B. 450 J
- C. 275 J
- D. 250 J
Explanation: m=10kgv=10m/sFret=-0.1J/mAt x= 20mF= -0.1 (20)=2NAt x=30mF=-0.1 (30)=3NAverage force=2+3/2 = 5/2 = 2.5NSo the average work done by the…
Correct answer: 475 J- A. 20 m/sec
- B. 12 m/sec
- C. 5 m/sec
- D. 10 m/s
Explanation: Given that, mass = 10kg. Vertical distance = 10m. Since starting from rest Initial velocity = 0 m/s. Work done = 500J.
Correct answer: 10 m/s- A. 500 J
- B. 5000 J
- C. 3750 J
- D. 475 J
Explanation: work energy theorem Work done in overcoming the air resistance=Loss in energyInitial KE = 0.5x m x v1^2 = 0.5 x 0.01 x 10^6 = 5000 J Final…
Correct answer: 3750 J- A. KE remain constant
- B. Momentum increases
- C. KE decreases
- D. All of these
Explanation: If work done is positive then kinetic energy increases. Since kinetic energy is directly proportional to the momentum therefore momentum…
Correct answer: Momentum increases- A. 1J
- B. 1.25J
- C. 1.5J
- D. l.75J
Explanation: Mass, m = 5g = 0.005 Kgh = 19.5 mx = 50 cm = 0.5 mv = 10 m/sThe change in the mechanical energy, ΔU = mg(h+x) + (1/2)mv2= 0.005 x 10(19.5…
Correct answer: 1.25J- A. Change in total energy
- B. Change in kinetic energy
- C. Change in power
- D. None of these
Explanation: The work-energy theorem states that the net work done by the forces on an object equals the change in its kinetic energy.
Correct answer: Change in kinetic energy- A. 1250J
- B. 1000J
- C. 1500J
- D. 2500J
Explanation: Given : m= 10 kg v= 10√x m/s and dv/dx = 5/√x Now we know the formula; w= ma w= m(dv/dt) = m(dv/dt)(dx/dx) w= mv (dv/dx) Now we will apply…
Correct answer: 2500J