• 4 months ago
Transcript
00:00Hi kids, today we will learn what is kinetic energy and how potential energy is converted
00:10to kinetic energy.
00:12So let's get started.
00:16Kinetic energy, energy possessed by an object due to its motion is called kinetic energy.
00:26We learned energy possessed by an object due to its position and also its weight is called
00:33its potential energy.
00:36The bodies in motion are capable of doing work and hence possess energy.
00:45The word kinetic comes from the word kinesis that means motion.
00:52The more the speed and mass of the moving body, the more is its kinetic energy.
00:59Let's see some examples.
01:02Here is a stone on a hilltop.
01:06What kind of energy does it possess?
01:09It possesses potential energy due to its position and weight.
01:15Its position is much above the ground level and it also has a lot of weight.
01:23When we will roll it down the hill, all the potential energy will change into kinetic
01:29energy, that is its motion.
01:33So the fast moving stone has kinetic energy.
01:38Here is another example.
01:41Water stored up in a dam possesses potential energy because of its position and its weight
01:52and its kinetic energy of the falling water that runs the turbine.
01:58Here is another example.
02:00A fast moving car.
02:03What kind of energy does it possess?
02:06It possesses a lot of kinetic energy due to its speed or motion.
02:14A fast moving car, if it hits anything, it can completely bang on it as it possesses
02:21a lot of kinetic energy.
02:26Why does a bullet fired from a gun possess a lot of energy?
02:31It is due to its motion or fast speed.
02:37It is because of the great kinetic energy that it possesses.
02:42It penetrates the target that it hits.
02:45Shooting arrow.
02:47What kind of energy does it possess?
02:50It has kinetic energy.
02:54But where does this kinetic energy in the arrow come from?
02:59It comes from the potential energy of the stretched bow.
03:04And bow possesses the potential energy due to its position, which is a stretched position.
03:14So kids, energy is neither created nor destroyed.
03:20It can be just converted from one form to another.
03:25Here, the muscular energy is being converted to the potential energy of the bow, which
03:32is being stretched.
03:35And then, when it's released, potential energy of the bow is being converted to kinetic energy
03:43of the arrow.
03:46Flowing water.
03:48What kind of energy does it possess?
03:52It possesses kinetic energy, which is the energy due to its motion.
03:59Where does this kinetic energy in the flowing water come from?
04:04Initially, the water is stored at height.
04:10It could be on the mountains or in dams, or it can be in the clouds too.
04:16Due to its position, it possesses potential energy.
04:21And when it is released from that position, its potential energy is converted to kinetic
04:28energy and gives motion to the water.
04:33And the kinetic energy of this water can be used to do a lot of work.
04:39Raft sails down the water due to kinetic energy.
04:47Dams generate electricity due to the kinetic energy of water.
04:53A strong windstorm blows off leaves from a tree.
04:58What kind of energy does it have?
05:02It possesses kinetic energy, that is, energy due to its motion.
05:10A fast-hitting hammer drives a nail in the board.
05:14How?
05:16Which energy does it possess?
05:19It has kinetic energy.
05:22And where does this kinetic energy in the hammer come from?
05:28It comes from the muscular energy.
05:32First of all, the muscular energy is converted into potential energy when the hammer is brought
05:40to a height.
05:42And then, this potential energy is converted to kinetic energy when it's made to hit the
05:51nail.
05:55Here are some examples where potential energy changes into kinetic energy.
06:02An apple, when on a tree, possesses the potential energy due to its position as it's on height.
06:13And when it falls, this potential energy changes into the kinetic energy, because which it
06:20falls with great speed.
06:24So kids, today we learned what is kinetic energy and what is the relationship between
06:32potential energy and kinetic energy.
06:36Now you may go ahead and take a quiz to learn more.
06:40Bye-bye!