Forces

• Non-contact forces do not require direct physical contact between objects to act on them.
• Weight = Mass x Gravitational Field Strength
• A force is any push or pull that changes the motion, shape or size of an object.
• Forces can be classified as contact forces (pushing/pulling) or non-contact forces (gravity).
• Contact forces are caused by direct physical interaction between objects.
• Contact forces are forces that occur when two or more objects come into contact with one another, such as friction, tension, air resistance, and weight.
• Frictional force is the force that opposes motion between surfaces in contact.
• Gravity is the force that pulls all matter towards one another, with Earth's gravity being the strongest gravitational field strength.
• Tension is the pulling force exerted by an object being pulled apart.
• Forces can be classified as either contact or non-contact forces.
• The weight of an object can be calculated by multiplying its mass (in kg) by the gravitational field strength (9.8 N/kg).
• Contact forces are exerted by one object directly onto another object.
• Friction is a type of contact force that opposes relative movement between two surfaces.