Student A takes 20 seconds, while student B takes 40 seconds to complete the same amount of work. Which of the following statements is correct in connection to A and B?
Student A has double the power of Student B
Power is the rate of doing work: P = W / t. Student A and Student B do the SAME amount of work W, but Student A takes 20 s while Student B takes 40 s.
So P₀ = W/20 and P₋ = W/40, giving P₀ / P₋ = (W/20) / (W/40) = 40/20 = 2. Student A's power is therefore twice that of Student B for the same work in half the time.
Hence, the answer is Student A has double the power of Student B.
Similar Questions
A device uses 1 kilowatt (kW) of power for 1 hour. How much energy does it consume?
A factory manager is comparing two machines that perform the same task. Machine A takes more time to complete the task than Machine B. Based on the definition of power, which factor should the manager consider to determine which machine is more powerful?
If a girl of weight 40 N climbs a rope with a power of 160 W for 20 seconds, up to what height can she reach?
Rate of doing work is called ________.
What is the SI unit of Power?
Important Questions from Power
Express the power dissipated in a 100 Ω resistor in dB relative to 1 mW, when the voltage across the resistor is 1.0 Vrms
An elevator weighing 500 kg is to be lifted up at a constant velocity of 0.25 m/s. What would be the minimum horsepower of the motor to be used? G = 9.8 m/s2 and there is no frictional loss.
A man of mass 80 kg climbs up 4 m high stairs in 10 sec. Find the power spent by the man. (Take g = 10 m/sec2)
How many units of electric power will be consumed by 4 motors of 0.5 HP each in 8 hours?
The power of a water pump is 2 kW. The amount of water (in litres) it can raise in one minute to a height of 10 m will be :
(g = 10 m/s 2 )
