A force is defined as what either pushes or pulls on an object. They're all measured in Newtons.(N) The heavier the object is, the stronger the force acting on in. Forces such as friction, and tension, only effect objects that they’re in directly in contact with. There are also forces that act from a distance, which include gravitational force, and magnetic force.
Some of these forces are defined below.
Friction:The force of friction is caused when the surfaces of objects are rubbed together. You can feel friction's presence as heat. When trying to move an object, this heat can waste some of the work you did.
rolling resistance friction
Tension: When something is pulled tightly a both ends, tension force is transmitted. Eg.
Gravity: When two objects that both have mass* are drawn to each other, this is what's defined as gravity. Gravity is measured in Newtons
*The amount of matter contained within an object is it's mass. Weight, however, is the level of gravity that's acting on an object. Eg.
For different forces, there are corresponding formulas to calculate them. To calculate the force of gravity,you'd multiply the weight of the object in kilograms, by 9.8 newtons. If you were calculating the force of gravity acting on an object that's weight was 5 kg, you would solve it like this.
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Forces
A force is defined as what either pushes or pulls on an object. They're all measured in Newtons.(N) The heavier the object is, the stronger the force acting on in. Forces such as friction, and tension, only effect objects that they’re in directly in contact with. There are also forces that act from a distance, which include gravitational force, and magnetic force.Some of these forces are defined below.
Friction:The force of friction is caused when the surfaces of objects are rubbed together. You can feel friction's presence as heat. When trying to move an object, this heat can waste some of the work you did.
Tension: When something is pulled tightly a both ends, tension force is transmitted.
Eg.
Gravity: When two objects that both have mass* are drawn to each other, this is what's defined as gravity. Gravity is measured in Newtons
*The amount of matter contained within an object is it's mass. Weight, however, is
the level of gravity that's acting on an object.
Eg.
For different forces, there are corresponding formulas to calculate them. To calculate the force of gravity,you'd multiply the weight of the object in kilograms, by 9.8 newtons. If you were calculating the force of gravity acting on an object that's weight was 5 kg, you would solve it like this.
9.8N x kg
9.8N x 5 kg = 49N
So, the object would be 49 newtons.
Try some practice questions here.