Balanced & Unbalanced Forces | Forces & Motion | Physics | FuseSchool

Balanced & Unbalanced Forces | Forces & Motion | Physics | FuseSchool

How do we find out whether the forces acting on an object are balanced or unbalanced? Learn in this video from the "Forces and Motion" chapter of the FuseSchool GCSE / K12 Physics.

00:00 - Introduction
Balanced forces. The famous English scientist Sir Isaac Newton, who lived between the 17th and 18th century, devised three laws of motion.

00:13 - Balanced forces
The first law states that if all the forces acting on an object are balanced, there will be no acceleration; meaning either constant velocity or the object remaining stationary but, what do we mean by balanced forces?

00:27 - Example
Let's look at the example of a horse. The first force we will consider is the force of gravity, this acts towards the centre of the earth. The size of the force of gravity is the horses weight. An arrow is drawn downwards from the horse towards the centre of the earth. If this were the only force acting on the horse, it would sink into the ground. As this is not the case, there must be a force opposing the force of gravity and arrows drawn in the opposite direction but equal in size.

01:00 - Reaction force
This force is called the reaction force. As the reaction force is the same size, but acts in the opposite direction to the horse's weight, these two forces are a balanced pair of forces. There are other forces acting on the horse.

01:17 - Other forces
The horse is moving forward, and therefore there must be a driving force from the horse's legs. The driving force though is opposed by forces trying to slow the horse down, and if the horse is traveling at a constant velocity, the force of friction and air resistance are equal in size, but opposite in direction to the driving force. The driving force is now balanced by friction and air resistance, a balanced pair of forces, and the horse now travels a constant velocity.

01:50 - Unbalanced forces
If though the horse accelerates the driving, force must be greater than friction and air resistance - the driving force is now no longer balanced by friction and air resistance. These forces are now unbalanced.

02:06 - Summary
So in summary, when the forces are balanced on an object - the object will either remain stationary or travel at velocity. When the forces are unbalanced, the object will either accelerate, meaning an increase in velocity, or decelerate, meaning a decreasing velocity.

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[diegocalderon]

Who else is watching this because this was a part of the assignment😂😂😂

[oli]

my online school teacher told us to watch this video

[cassielacey]

I have a feeling that most of us in middle school ( “I’m totally not in middle school watching this” ) 😂🤣

[lrdfkp]

Leaving my mark on this video
Hope anyone who sees this passes their class

[jala]

Here’s something so you don’t have to work hard


When two forces acting on an object are equal in size but act in opposite directions, we say that they are balanced forces . If the forces on an object are balanced or if there are no forces acting on it, this is what happens. a moving object continues to move at the same speed and in the same direction.



(THE SCHOOLS ARE GOING TO BE SUSPICIOUS WHEN EVERYONE HAS THE SAME ANSWERS

[lorenzothepasta]

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[elijahtucker]

tldr version: balanced forces 0:25 unbalanced forces 1:48

here is answers hopefully they help QUESTION:What is one example from the video of a balanced force? Be specific? ANSWER:A horses weight when it stands or walks

QUESTION:What is one example from the video of an unbalanced force? Be specific. ANSWER:A horse that is running

QUESTION:Summarize the video in 3-5 sentences. ANSWER:well this video teaches physics and forces even motion, motion is when something is moving and motion can help some things and ruin others

[XauHD]

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Like me XD

[arobeplays]

I am watching this for school, and it is really helpful!

[shantisudiana]

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[angelinacortes]

ur voice just is so cool, and this is just bc of online teacher making me watch this btw,

[sakurafeshi]

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[aamenap]

science teachers always be assigning us videos to watch that were made like 6 years ago

[Thermospecialist]

Newton's  first law is wrongly given here. Instead it says that an object persists in its state of motion, unless acted upon by an external force. There is nothing about balanced forces.

In 1:25, the driving force, causing an acceleration, is opposed by an equal inertial force as per Newton's 2nd law, which is ignored here. Hence we have acceleration under balance of forces.

In 1:56, when the horse is accelerating, this inertial force must be added to the air resistance and friction force, making the driving force equally  larger, so in 2:02 we still have balance of forces, as required by Newton's 3d law.

The confusing thing then becomes how the horse can accelerate if no unbalanced force acts on it? In standard physics this is due to calling the inertial force a pseudo, or fictitous force, thus of a different (unknown) nature than the "real" forces, and therefore left out of the force equation, thus getting an unbalanced force.

What is ignored in the textbooks is the flow of energy, in this case from the horse's muscles to the surroundings, in which it disperses - friction and air resistance generate heat. This flow of energy is the real cause of the motion, as explained here:
.

[oliverpalin]

This contains useful information. Thank you. This will help me in my exams.

[shereenabbas]

The teacher made the whole class watch this like 12 times

[lorenzothepasta]

This was very explanatory and informative. THANK YOU SO MUCH!!

[SECRETFRUITS]

Tysm man this was helpful as u meant by reaction force is it also called constant force?

[christinazechariah]

Thanks for this great video. It was very helpful(:

[mars]

This helped me get an A for home work twice!