What happened after sometime, one team wins and other loose. Why? Its due to the fact that the winning team applied more force towards them and the opposite to force applied by losing team. For example, winning team, applied force F1 and losing team F2 and if F1 will be more than F2 then team applying force F1 will win.

In this case, there are two forces F1 and F2 and both are not equal. Thus these types of forces which are not equal and due to which there is change in the rest or motion and there may be change in the size or shape, are known as Unbalanced forces. Change is size or shape means, if there are two forces applied on a football but in opposite direction then there be change in shape of football.

Unbalanced Forces:

Thus, unbalanced forces means the forces wchich may have following two effects:

a) change in state of rest or motion,

b) Change in size and shape of object.

Balanced Forces:

Suppose if in tug of war game, both sides apply same force that F1 equals to F2. Then there will be no winner or looser. If there is a block, and two persons are pushing it from opposite sides with force F1 and F2 respectively. If F1 and F2 are equal, will the block move to either side. The answer is NO.

So those forces which are equal and opposite are known as balanced forces. But these forces may change the shape or size of the object.

This is all about the difference between the balanced and unbalanced forces. I have you have understood the differences. Do read about the interesting story of force and the story of Types of Force.

The post Difference between Balanced and Unbalanced Forces first appeared on Winner Science.

Last time we have discussed the story of force and its effects. Today we will discuss types of forces. Let’s begin,

The five friends A, B, C, D, and E asked the sixth friend F that is force, Hey friend force, you have explained the meaning of yours and also your effects means the story of force and its effects. But can you explain

1. Which type of force is acting on football when we kick the ball?
2. Why football stop automatically after kicking and after moving and rolling for some time?
3. Why football came back from air to ground again?

All 5 asked, we have so many queries, please explain.

The friend force F explains, dear friends, I will answer all your queries one by one. Do you know I have 2 more siblings or types? The name of the first one is the Contact force and the name of the second one is a non-contact force.

First let me explain about contact forces: As you have asked about what type of force is acting on the football when you kicked the same. Here your body means your foot is in contact with the football. So, these types of forces where the two bodies are in contact with each other are known as contact forces.

A) There are following types of contact forces:

1. Muscular force: like you are kicking the ball, so you are using muscles of the body. These types of contact forces are known as muscular forces.

2. Frictional force: your second query was why football stops automatically after kicking and after moving and rolling for some time? This is due to the force of friction. This is the force acted by the ground in opposite direction to the movement of the ball.  Here again ground and football are in contact so these are contact forces. Similarly, if you stop pedaling a bicycle, it will stop automatically after some time. Thus due to friction that is opposing force, the state of motion of objects changed. Thus, the second type of Contact Force is Frictional Force.

Now there are types of forces where the two bodies are not in contact with each other are known as non-contact forces.

B) Now let us discuss about Non-Contact Forces:

1. Gravitational Force: Now dear friends, come to your third query that is Why does football come back from air to the ground again? This is due to the force of gravity or gravitational force. You must have heard about the story of great Scientist Newton and apple. He concluded that Apple has fallen due to the force of gravity. Similarly, football came back from air to ground again? This is known as the force of gravity. Similarly, if you through up anything in the air, it will come back towards earth due to the force of gravity. Here the earth is pulling down the ball without touching the objects. Similarly, every object in the universe interacts or exerts a force on another object, and then this type of force is known as Gravitational force. So these types of forces are Non-contact forces. There are two more non-contact forces. Can you tell?

2. Friend A told spontaneously that, yes a magnet can attract another magnet or iron pieces without touching it. Force F told, very Good my dear friend, this type of force is known as magnetic force.

3. You may have observed that when you comb in dry hair if you place the comb near a small piece of papers, then papers got attracted towards the comb. These are due to charges. Similarly, charges can attract and repel each other without touching each other. These are known as Electrostatic forces.

So dear friends, I hope you must have learned about my two types and further three types. Let’s revise. So Friend A, what are the two types of Forces? Friend A told that two types of forces:

1. Contact forces
2. Non contact forces

Very good, Friend B, please tell me about types of contact forces. B told that there are two types of Contact forces:

Contact Forces: a) Muscular Force and b) Frictional Force

Wow, that’s great now friends C, D, and E tell me three types of non-contact forces. All three told the following respectively:

Non Contact forces: a) Gravitational force, b) Magnetic force and c) Electrostatic force.

Excellent, Force F appreciated everyone and told that you all have understood the meaning of force and its types. Do you? Please post in the comments section. Thanks.

The post Story of Types of Forces first appeared on Winner Science.

Have you ever heard the story of force and its effect? I will narrate the same. Once upon a time, there were five friends named A, B, C, D, and E.

They were playing in the playground with a football. Friend A told to everyone that football is at Rest (means not moving) and I will kick it and will change its state to motion. Thus I am strongest.

Second Friend B told that I can stop the ball or decrease the speed of football. Thus I am strongest.

Third friend C told that I can change the direction of moving the football with my kick. Thus I am strongest.

The fourth friend told that I can change the shape of football using my hands. Thus I am strongest.

The fifth friend told that I can do each and everything of all of you mentioned. Thus I am the strongest one.

So, every friend felt that he is stronger than others.

Then a sixth person came and told that oh my dear friends, whatever you all are doing its due to me. Everyone called me FORCE. Due to me,

1. A may change the state of football from Rest to motion,
2. B may decrease the speed of ball,
3. C may change the direction of motion,
4. D may change the shape of ball.
5. E may do any some of the above or all.

These are known as my Effects or effects of Force.

Then friends asked how do you do all things.

Force F told that I can do it either by Push or pull. Like shutting a door is a push and opening through the inside room is a pull. Opening a drawer is a pull and closing is a push. You all can identify different daily life examples of push or pull. Do you know, even our earth uses me that is known as force of gravity and due to which all other objects are attracted towards earth.

One final point that you all should know that force always requires at least two objects to interact with each other. In all the above cases like shutting or opening a door or drawer, there is the interaction between door and person or drawer and person. In gravity, the earth and another object interact.

Finally, Force F asked all friends I hope you have understood the meaning of Force, its effects, and the type of Force. All five friends thanked Force and started playing again.

Here is the link to our Youtube video on the story of Force:

The post Story of Force and its effects first appeared on Winner Science.

But do you know that the Newton’s second law is known as the real law of the motion. Let us prove it by showing that the Newton’s first law is contained in the second law.

Proof: let us take an isolated system that is system isolated or free from external forces.

From this law F = ma, where F is force, m is mass of object and a = acceleration.

As the system is isolated, thus F =0, therefore above equation becomes:

ma = 0,

but m can not be zero, thus a= 0 that is acceleration is zero of the object.

It is only possible when the object is at rest or in uniform motion and this is nothing but Newton’s first law.

It proves that the Newton’s first law is contained in the second law and thus proves that the Newton’s second law is the real law of motion.

The post Why Newton’s second law is the real law of motion first appeared on Winner Science.

But we consider force in a straight line motion or in linear motion. If there is a rotational motion, even then we can apply a force. For example, when you rotate a handle of a door, then according to you it moves with the help of external force applied by you, but according to a physicist it moves according to  the torque provided by you.

Thus in simple words torque is provided to move a body in rotation and force is provided to move a body in linear motion.

This is the major and simple difference between force and torque.

The post Difference between force and torque first appeared on Winner Science.

Conservative forces: A force is said to be conservative if work done by the force or against the force to move an object through a certain distance depends only upon the initial and final positions of the body not on path followed by the object between initial and final positions.

For example: gravitational force, magnetic force between two magnetic poles, electrostatic force between two electric charges are examples of conservative forces.

Work done in moving an object through round trip or closed path is always zero.

Non conservative forces: A force is said to be non conservative force if work done by the force or against the force to move an object through a certain distance depends on the nature of the path not on the initial and final positions.

For example: frictional forces, induction force in a cyclotron.

These are the differences between the conservative and non conservative forces. If you know more examples, then please share with our readers.

The post Difference between conservative and non conservative forces first appeared on Winner Science.

1. Mud through rotating wheels: we have seen that the rotating wheels of a vehicle throughout mud in a tangential direction. This is due to inertia of direction. This is the reason that the mud guards are provided in vehicles over the wheels to stop this mud so that to protect the clothes.
2. Our protection through umbrella: The second example of inertia of direction is protection of us by umbrella. The rain drops falling vertically downwards cannot change their direction of motion and so cannot wet us when the umbrella is up.
3. Tangential movement of untied stone: The third example of inertia of direction is the tangential movement of a stone. This happened when a stone tied to one end of a string is whirled and if the string or thread suddenly breaks then the stone flies off along the tangent to the circle. This is due to the reason that the pull in the thread was forcing the stone to move in a circle. As soon as the thread breaks, the pull vanishes. The stone in a bid move along the straight line moves tangentially due to inertia of direction.

These are the 3 examples of the inertia of direction. If you know more, please share with us.

The post 3 examples of Inertia of direction first appeared on Winner Science.

1. First example of inertia of rest: Fall of dust particles from a durries or cloth: We all have seen that the dust particles in a durries or cloth fall off when it is beaten with a stick. This is due to the reason that the beating results in motion of durries but the dust particles remain at rest. Thus dust particles fall off. This is one of the examples of inertia of rest.

Also read: Types of inertia

2. Second example of inertia of rest: Fall of rider backwards: You must have also noticed that the rider of a horse falls backwards, when a horse starts suddenly. This is also due to inertia of rest of upper part of the body of the rider.

3. Third example of inertia of rest: Fall of coin into the glass: Let us play a simple game or experiment to understand the inertia of rest.

Things required: an empty glass, a coin and a cardboard.

Now place the cardboard on the top of glass and then place the coin on the cardboard. Strike the cardboard with the suddenly with the finger. If you have done it perfectly, then coin will fall into the glass. Do you know why this happens? This happens due to inertia of rest. As the coin was at rest, it remains at rest so it does not move with the cardboard.

These are the 3 examples of the inertia of rest. If you know more examples, then please share with us.

Note: If you want the e books of our articles, then please see the Winnerscience books page. These books are available at a price of Rupees 10 for Indian readers and half a dollar for outside India.

The post 3 examples of Inertia of rest first appeared on Winner Science.

For eg. Hitting a ball with bat fining a gun etc.

An Impulsive force doe snot remain constant but changes, firstly from zero to max and then from max. to zero.

So it is not possible to measure the exact value of force. Hence in such cases, we measure the total effect of force known as Impulse.

So Impulse of a force is defined as the measure of total effect of force. It is given by the product of force and time.

 Impulse = F´t

Acc. To Newton’s 2^nd Law

                                                                   F = dp/dt

Þ                                                            Fdt = dp

Integrating both sides with in the respective limits and solving, we get:

                                                            F[t]_o^t = [p]^p1_p2

                                                           F[t – o] = [p₂ – p₁]

                                                                    Ft = p₂ – p₁

Impulse is a vector quantity and it is also measured by the total change in the linear momentum. Its direction is same as that of force.

The dimension formula for Impulse is [MLT^-1] The S.I unit of Impulse is N sec and C.G.S unit is dyne sec.

The equation Impulse = Change in momentum is also known as the Impulse momentum Theorem.

Application:

(i) A cricket player lowers has hands while catching the ball : by doing so the time of impact increases and hence the effect of force decreases.

(ii) When a person falls from a certain height on floor, he receives more injuries as compared to falling on a heap of sand. It is because the Cemented floor does not yield whereas the sand yield there by increasing the time of impact hence decreasing the impact of force.

(iii) The shock absorbers provided in the vehicle helps to travel smoothly on an uneven road. It is because the shockers increases the time of impulse which reduces the force.

The post impulse force and its applications first appeared on Winner Science.

According to the Newton’s 2^nd Law of motion, the rate of change of linear momentum of a body is directly proportional to the applied external force and in the direction of force.

It means that the linear momentum will change faster when a bigger force is applied.

Consider a body of mass ‘m’ moving with velocity v.

The linear momentum of a body is given by:

p = mv

Now According to Newton’s 2^nd Law of Motion:

Force is directly proportional to rate of change of momnetum, that is

F α dp/dt

F  = k dp/dt

F = k d(mv)/dt

F = k md(v)/dt

F = k ma

Experimentally k =1

F = k ma

Which is the required equation of force.

The post Derive relation F = ma from Newton 2nd Law of Motion first appeared on Winner Science.