Identifying Forces
Forces at Play
Forces are all around us and although we can’t see them acting we can see the outcome whether we realise it or not.
A force can make something:
Forces as Play Cont.
A force rarely works alone. There are many types of forces within the universe and they often act together.
Gravity Force
A force of attraction that objects have on one another due to their masses.
On Earth it is a force that pulls objects towards the centre of the Earth. For example if you let go of an object it hits the ground thanks to gravity.
Normal Force
A bag on the table stays still. It doesn’t move because the gravity that pulls the object down is equal to the force on the table pushing up. The force that keeps the bag still is named normal.
Applied Force
The force that is acting on an object. For example, pushing keyboard buttons, tapping your smartphone, closing a door or moving an object.
Friction Force
Force that acts to oppose the motion between two surfaces as they move over each other. Different surfaces or objects offer less or more friction. For example, a ball will roll easier across a concrete floor than it will over a carpet floor. The more friction there is the harder it is too move an object.
Air Resistance Force
Friction between a moving object and the air it is moving through. As with normal friction it changes, slows or stops an object’s motion.
Buoyancy Force
An upward force exerted on an object by the fluid it is placed in. Like air resistance it may change, slow or stop an object’s motion.
Elastic Force
A reactionary force that is produced when springing object is stretched or compressed. The object returns to its original form after pulling or stretching.
Elastic force is repulsive when a spring is pressed for example, someone lying on a mattress.
It is attractive when spring is stretched for example, a rubber band.
Magnetic Force
A force that can pull and stick some objects to a magnet. Magnets produce a magnetic field and they pull on some metals such as iron and nickel. They don’t pull on objects such as wood, plastic, and gold.
If you use two magnets you may cause them to attract or repel each other. This is known as magnetism.
Tension Force
Tension is a force that is directed on another object. A string, a cable or similar objects creates this force. For example walking a dog with a lead, opening a blind with a string or a tug of war.
Electrostatic Force
Force of attraction or repulsion between two charged objects (particles). Like charge repel whereas opposite charges attract.