Advertisements
Advertisements
Question
Calculate the work done when:
A car is moved on a rough road through 30 m against a frictional resistance of 75 N.
Advertisements
Solution
Resisting force = 75 N; Distance moved = 30 m
∴ Work done = 75 × 30 J = 2250 J.
RELATED QUESTIONS
kWh is the unit of ______.
Name the quality which is measured in eV
State the factors on which moment of force about a point depends.
State the condition when the work done by a force is negative. Explain with the help of examples.
A bullet fired against a window glass pane makes a hole in it without any cracks while a stone striking the same glass pane smashes it; explain with reason.
What do you understand by work? Is work a scalar or a vector quantity?
State the S.I. and C.G.S. units of energy. How are they related?
A coolie carrying a load on his head and moving on a frictionless horizontal platform does no work. Explain the reason why.
A machine raises a load of 750 N through a height of 16 m in 5 seconds. Calculate the power at which the machine works.
A boy weighing 50 kgf climbs up from the first floor at a height of 3 m above the ground to the third floor at a height of 9 m above the ground. What will be the increase in his gravitational potential energy? (Take g = 10 N kg-1).
