Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
(i) Work done by each man = mgh
= 50 × 10 × 2
= 1000 J
(ii) Work done in first case = `w/t_1`
= `1000/20`
= 50 W
Work done in second case = `w/t_2`
= `1000/50`
= 20 W
APPEARS IN
संबंधित प्रश्न
Draw a simplified diagram of a lemon crusher, indicting of load and effort
When a body moves in a circular path, how much work is done by the body? Give reason.
(Hint: The body is acted upon by the centripetal force.)
State and define the S.I. unit of work.
What physical quantity does the electron volt (eV) measure? How is it related to the S.I. unit of that quality?
kWh is the unit of ______.
A mechanic can open a nut by applying a force of 200 N while using a lever handle of 50 cm length. How long handle is required if he wants to open it by applying a force of only 50 N?
An engine does 54,000 J of work by exerting a force of 6000 N on it. What is the displacement in the direction of the force?
How is 1 kgf related to the SI unit of force?
A force F when acts on a body, displace it by a distance d in a direction at an angle θ with the direction of the force. Write down the expression for the work done by the force.
