Advertisements
Advertisements
प्रश्न
A rocket is moving up with a velocity v. If the velocity of this rocket is suddenly tripled, what will be the ratio of two kinetic energies?
Advertisements
उत्तर
Let the mass of the rocket be m.
The kinetic energy of a rocket when it moves with velocity v,
`"K"_1 = 1/2"mv"^2`
The kinetic energy of rocket when it moves with velocity 3v,
APPEARS IN
संबंधित प्रश्न
Fill in the blank
Green plants convert _________ energy into chemical energy.
Energy can exist in several forms and may change from one form to another. State the energy changes that occur in a car going uphill.
State the energy changes in the following case while in use:
loudspeaker
Avinash can run with a speed of 8 m s–1 against the frictional force of 10 N, and Kapil can move with a speed of 3 m s–1 against the frictional force of 25 N. Who is more powerful and why?
Can any object have mechanical energy even if its momentum is zero? Explain.
Can any object have momentum even if its mechanical energy is zero? Explain
The power of a motor pump is 2 kW. How much water per. the minute the pump can raise to a height of 10 m? (Given g = 10m s−2)
If an electric iron of 1200 W is used for 30 minutes every day, find electric energy consumed in the month of April.
Four men lift a 250 kg box to a height of 1 m and hold it without raising or lowering it.
(a) How much work is done by the men in lifting the box?
(b) How much work do they do in just holding it?
(c) Why do they get tired while holding it? (g = 10 m s–2)
State the energy changes in the following case while in use:
A glowing electric bulb
