Power MCQ

Test your knowledge with important Power MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more Power MCQs at Bissoy

• Power is the time derivative of which quantity?
  ক

  Energy

  খ

  Acceleration

  গ

  Velocity

  ঘ

  Position
• The force applied on a body can be given as F = 4i + 2j + 6k. The displacement of the body is given by s = 3i + 9k. Calculate the power at t = 2 seconds.
  ক

  66 W

  খ

  33 W

  গ

  30 W

  ঘ

  15 W
• Which of the following is the correct formula of Bond’s law?
  ক

  \(\frac {P}{m}\) = kb\((\frac {1}{\sqrt {D_{sb}}} + \frac {1}{\sqrt {D_{sa}}}) \)

  খ

  P = kb\((\frac {1}{\sqrt {D_{sb}}} – \frac {1}{\sqrt {D_{sa}}}) \)

  গ

  \(\frac {P}{m}\) = kb\((\frac {1}{\sqrt {D_{sb}}} – \frac {1}{\sqrt {D_{sa}}}) \)

  ঘ

  P = kb\((\frac {1}{\sqrt {D_{sb}}} + \frac {1}{\sqrt {D_{sa}}}) \)
• The SI unit of power is?
  ক

  kW(kilo-watt)

  খ

  J/s(joules per second)
• Calculate the work done in a resistor of 20 ohm carrying 5A of current in 3 hours.
  ক

  1.5J

  খ

  15J

  গ

  1.5kWh

  ঘ

  15kWh
• Calculate the power across each 10 ohm resistance.
  ক

  1000kW, 1000kW

  খ

  1kW, 1kW

  গ

  100W, 100W

  ঘ

  100kW, 100kW
• Calculate the power across each 20 ohm resistance.
  ক

  1000W, 1000W

  খ

  500W, 500W

  গ

  1000kW, 1000kW

  ঘ

  500kW, 500kW
• A current of 5A flows in a resistor of 2 ohms. Calculate the energy dissipated in 300 seconds in the resistor.
  ক

  15kJ

  খ

  15000kJ

  গ

  1500J

  ঘ

  15J
• Calculate the power in the 20 ohm resistance.
  ক

  2000kW

  খ

  2kW

  গ

  200kW

  ঘ

  2W
• Kilowatt-hour(kWh) is a unit of?
  ক

  Current

  খ

  Power

  গ

  Energy

  ঘ

  Resistance
• A 250V bulb passes a current of 0.3A. Calculate the power in the lamp.
  ক

  75W

  খ

  50W

  গ

  25W

  ঘ

  90W
• The force required to tow a vehicle at constant velocity is directly proportional to the magnitude of velocity raised to the first power. It requires 1000 W to tow with a velocity of 10 m/s. How much power is required to tow at a velocity of 8 m/s?
  ক

  320 W

  খ

  640 W

  গ

  160 W

  ঘ

  80 W
• A body of mass 3 kg starts from rest with a uniform acceleration of unknown magnitude. If the body has a velocity of 30 m/s in 6 seconds, what is the power consumed in 3 seconds?
  ক

  125 W

  খ

  225 W

  গ

  325 W

  ঘ

  425 W
• A 200 kg wagon climbs up a hill of slope 30-degrees in 1 minute at a speed of 36 km/h. How much power is delivered by the engine if the frictional force is 25% of the weight of the car? (Assume g = 10m/s2)
  ক

  25 kW

  খ

  50 kW

  গ

  100 kW

  ঘ

  125 kW
• A 200 kg wagon climbs up a hill of slope 30-degrees in 1 minute at a speed of 10 m/s. How much power is delivered by the engine? (Assume g = 10m/s2)
  ক

  10 kW

  খ

  20 kW

  গ

  30 kW

  ঘ

  40 kW
• 1000 kW of power is supplied to a motor. 90% of this is transmitted to a machine operating at 80% efficiency. The machine lifts an object of 10-tons with a velocity _____ m/s. (Assume g = 10m/s2)
  ক

  2

  খ

  4

  গ

  6

  ঘ

  8
• A 2-ton vehicle travels at 20m/s on a road where the frictional force is 10% of the weight of the vehicle. What is the power required? (Assume g = 10m/s2)
  ক

  220 kW

  খ

  240 kW

  গ

  420 kW

  ঘ

  440 kW
• A machine has a power of 20kW. How long will it take for it to lift a body of mass 10kg from the ground to a height of 100m? (Assume g = 10m/s2)
  ক

  1 second

  খ

  2 seconds

  গ

  3 seconds

  ঘ

  4 seconds
• A motor is used to pump water from a depth of 5 m to fill a volume of 10 cubic meters in 5 minutes. If 50% of the power is wasted, what is the power of the motor? (Assume g = 10m/s2)
  ক

  1000/3 W

  খ

  3000/3 W

  গ

  5000/3 W

  ঘ

  10000/3 W
• A motor is used to deliver water through a pipe. Let the motor have a power P initially. To double the rate of flow of water through the pipe, the power is increased to P’. What is the value of P’/P?
  ক

  2

  খ

  4

  গ

  6

  ঘ

  8
• A machine gun fires 360 bullets per minute. Each bullet has a mass of 5 grams and travels at 600 m/s. What is the power of the gun? (Assume no loss of energy and 100% power transmission)
  ক

  300 W

  খ

  600 W

  গ

  900 W

  ঘ

  1800 W
• What are the units of power?
  ক

  Newton

  খ

  Joule

  গ

  Watt

  ঘ

  No units