When ever you want to move, you need to apply a force. When you throw a ball, you need to apply a force.
Balanced and Un-
When the forces acting on an object are equal, but in opposite directions we say that they are balanced.
When these two forces equal out, the object is at equilibrium.
Every stationary is in equilibrium. When you sit in a chair, you are in equilibrium.
The support force acting on you balances out your weight.
As the name suggests, unbalanced forces is where one force is greater than the other, acting in the opposite direction.
The Driving force of an engine is greater than the resistive force from air resistance and friction.
The clean and jerk is a popular weighting move. However there is a large amount of physics and forces acting here.
We’ll look at the basics for now
At the start of this lift, there is a greater force. The bar weighs 96 kg. This means there is 960 Newtons of force pushing down on the bar.
At the stage, the forces are unbalanced. The person is applying more than 960 Newtons and lifting the bar.
At the top of her lift, the forces are balanced.
Once she lets go of the bar, the forces become unbalanced and the bar falls to the floor.
To the left is the entire clean and jerk.
The world record for clean and jerk is 266 kg
We can use unbalanced forces to affect speed. A rocket engine will propel the object forward very quickly, while a parachute, will slow the car down.
The Earth exerts a force on the Moon. The force of gravity acting on the Moon keeps the Moon in orbit around the Earth.
It’s the same force which pulls a ball to the ground when it falls off a table.
It doesn't change the speed of the object, but does change the direction of motion.
When on a motor bike, you lean to one side to turn corners. Turning the bike, creates friction between the tyres and the road, changing the direction of the bike.
Questions
Short Answer Questions
1. A driver and his passenger get out of their car, that has run out of gas on the street. They cannot agree on which gas station is closer, so they begin pushing with equal force on opposite ends of the car.
a) Make a sketch of this car-
b) Use you sketch to explain whether the forces on the car are balanced or unbalanced.
2. A floatplane lands on a harbour. When the float touches the water, the planes slows down.
a) Are the forces on the plane balanced or unbalanced? Explain.
b) What type of force does that water exert on the plane’s floats, which causes the motion of the plane to slow?
c) Sketch the floatplane at the moment of landing on the water using arrows to represent the forces on the plane.
3. Copy and Complete the sentence below.
If the forces on an object are the same ______ but act in ________ directions they are balanced. This is called _______. The forces acting on any stationary object are ___________. If the forces on an object are _______ are unbalanced the ______ will change. If they _____ force is bigger than the ________ force it slows down.
4.
5. Define the terms Resistive and Driving force. Explain how these to forces interact with
6.
