Advertisements
Advertisements
प्रश्न
Give an example
Electrical energy changes to heat energy.
Advertisements
उत्तर
Electric iron
APPEARS IN
संबंधित प्रश्न
How is work related to energy?
Express joule in terms of erg.
Differentiate between energy and power.
A machine raises a load of 750 N through a height of 16 m in 5 s. calculate:
- energy spent by machine,
- power at which the machine works.
Is work a scalar or a vector quantity?
A max X goes to the top of a building by a vertical spiral staircase. Another man Y of the same mass goes to the top of the same building by a slanting ladder. Which of the two does more work against gravity and why?
A bullet is of mass 'm' g and is moving with a velocity 'v' m/s. Find the kinetic energy of the bullet when
(a) The mass is doubled,
(b) The velocity is tripled.
State the energy changes which take place when A piece of magnesium wire is burnt in a jar of oxygen.
A coolie is pushing a box weighing 1500 N up an inclined plane 7.5 m long on to a platform, 2.5 m above the ground.
(i) Calculate the mechanical advantage of the inclined plane. (ii) Calculate the effort applied by the coolie.
(iii) In actual practice, the coolie needs to apply more effort than what is calculated. Give one reason why you think the coolie needs to apply more effort.
