Work, Force And Energy
Transcript
00:00Hey Kitty, I am preparing to teach our audiences about this exciting subject on work, force
00:12and energy.
00:13Hey friends, so without wasting much energy, let us work on understanding this topic and
00:22force ourselves to expand our knowledge about this academic subject called work, force and
00:29energy.
00:30Zoom in!
00:34Our daily lives involve numerous tasks such as cleaning the house, working at a factory
00:40or playing in the field.
00:43And all these activities include several movements that need you to push or pull objects that
00:49may react differently.
00:53Yes, these activities can either set an object in motion, shift its direction, change its
01:00shape or put that object back into the resting position.
01:06And this movement of push and pull applied on an object is called force.
01:13However, the force is different in every scenario and depends on many other elements that are
01:21divided into two categories known as contact force and non-contact force.
01:28And what are they?
01:30Well, when two or more objects come in contact with each other during the interaction, the
01:38force is called a contact force.
01:42This contact force is further divided into various types such as applied force, frictional
01:49force, normal force etc.
01:53And some of the examples of contact force are a person pushing a huge wooden box, a
02:01person skating on a rough floor stopped by the friction, a table supporting a vase kept
02:09on it by exerting an upward force and much more.
02:16On the other hand, the non-contact force is the opposite of the contact force, meaning
02:23during a non-contact force, two objects do not come into physical contact with each other
02:30during the interaction.
02:32The main types of non-contact force are gravitational, electrostatic and magnetic.
02:41Some of the examples of non-contact force are an apple falling from a tree, a football
02:48kicked high in the air falling towards earth, an iron nail attracted to a magnet, pieces
02:57of paper attracted towards your ruler or comb when rubbed.
03:04And to understand both the forces quantitatively, the force is measured in the unit Newton.
03:14But the application of force does not end the topic, in fact it takes us to the next
03:21step of force applied, called work.
03:25When a force is applied to an object, it results in the movement of an object and when this
03:32happens the work is said to be done, and even the work performed can differ in various
03:39forms.
03:40Yes, the work could be either positive, which means the force is in the same direction as
03:47the displacement of an object, or it could be negative, indicating the displacement of
03:53an object is opposite to the direction of the force applied.
03:58Or else, it could be zero, which means the force and displacement are perpendicular to
04:06each other, in other words, there is no displacement of an object.
04:13So to understand the kind of work done, we calculate it using the formula, work is equal
04:21to force into distance, and the standard unit of measurement for work is Joule.
04:31But remember my friends, in order to apply the force and perform the work, we need the
04:38ability to do it, and that ability to perform the work is known as energy.
04:46Yes, my dear friends, without energy, you won't be able to perform even the simplest
04:53task.
04:54So, it's essential to refill yourself by a regular supply of energy that can be obtained
05:01from the food we eat, like green vegetables, fruits and nuts, that gives you the required
05:09strength to perform your daily work and keeps you healthy and wise.
05:14Trivia Time!
05:17Did you know, the gravitational force is the one that keeps the earth orbiting around the
05:22sun?
05:24Also, the earth is like one strong bar magnet, which has a magnetic north and south, which
05:32the needle on a compass represents too.
05:37Hope you learnt something new in today's episode.
05:40Until next time, it's me Dr. Binox, Zooming out!
05:51Ah, never mind!