Advertisements
Advertisements
Question
State the condition when the work done by the force is positive
Advertisements
Solution
Work done by a force is positive when the displacement is in the direction of the force.
RELATED QUESTIONS
A man spends 7.4 KJ energy in displacing a body by 74 m in the direction in which he applies force in 2.5 s. Calculate the force applied.
Name the quality which is measured in eV
A body of mass m is moving with a uniform velocity u. A force is applied on the body due to which its velocity changes from u to v. How much work is being done by the force?
What is meant by a rotatory motion? Give one example.
State the condition when the work done by a force is negative. Explain with the help of examples.
A man raises a box of mass 50 kg to a height of 2 m in 20s, while another man raises the same box to the same height in 50s. Calculated:
- the work done, and
- the power developed by each man. Take g = 10 N kg-1.
State and define the unit of force in the S.I. system.
Justify the statement. “Power can be expressed as the product of force and velocity.”
State the S.I. and C.G.S. units of energy. How are they related?
