Advertisements
Advertisements
प्रश्न
Obtain an expression for the kinetic energy of a body of mass m moving with a velocity v?
Advertisements
उत्तर
Let the body is brought to rest by a retarding force F after traveling a distance s.
From relation v2 = u2 + 2aS, retardation a =`"v"^2/(2"S")`
∴ Retarding force F = ma `="m"xx"v"^2/(2"S") =1/2("mv"^2) /"S"`
Work done W = F × S `=1/2("mv"^2)/"S"xx"S"=1/2"mv"^2`
Hence K.E = `1/2` mv2
संबंधित प्रश्न
State two advantages of geothermal energy.
Geothermal energy is produced by the:
(a) fission of radioactive materials
(b) burning of coal inside the coal mines
(c) combustion of natural gas deep inside the earth
(d) fusion of radioactive substances
Select the correct alternatives
The energy stored in an electric cell is
A body of mass m falls down through a height h. Obtain an expression for the work done by the force of gravity.
Name the form of energy in which potential energy can change.
What is the main energy transformation that occur in:
Charging of a battery.
State the energy changes which take place when:
A toy car spring is wound and car is made to run on level floor.
Give one example when:
Heat energy changes to kinetic energy.
A body of mass m is taken from a height h to 2h. What is the increase in its potential energy?
In a hydroelectric power station, 1000 kg of water is allowed to drop through a height of 100 m in 1 sec. If the conversion of potential energy to electric energy is 60%. Calculate the power output. [Take: g = 10m/sec2]
