Question Text
Question 2 :
An engine develops 10 kW of power. How much time will it take to lift a mass of 200kg to a height of 40m (g = 10 $ms^{-2}$)?
Question 3 :
What does the slope of work-time curve at any instant represent?
Question 4 :
Which of the following must be known in order to determine the power output of an automobile? <br>
Question 6 :
If the force applied is $F$ and the velocity gained is $v$, then the power developed is:
Question 7 :
A machine gun fires $420$ bullets $per\ minute$. The velocity of each of the bullets is $300 m s^{-1}$ and the mass of each bullet is $1 gm$. The power of machine gun is:
Question 10 :
A man can lift a block of mass of 50 kg up to a height of 2 m in 2 seconds. Calculate the power developed by the man to lift the block.
Question 11 :
How much energy does a 60W electric bulbtransfer in 1 minute?
Question 15 :
A car of mass $2,000 kg$ is lifted up a distance of $30 m$ by a crane in $1\ minute$. A second crane does the same job in $2\ minutes$. The power supplied by second crane is:
Question 16 :
Fill in the blanks:One kilowatt is equal to ________ horse power.
Question 18 :
If a man of $30$ kilograms climbs stairs in $4$ seconds when height of stairs is $5$ meters, power output produced will be:<br/>
Question 19 :
In our household applications, commercial unit of electricity is used. One unit is equal to:
Question 20 :
A man weighing 600 N carries a load of 150 N up the stairs 6 m high in 15 seconds. His power will be: