Forces - Page 1 Notes (Science Revision)

Flashcards covering key concepts from Page 1 notes: force definitions, measurement, representation, inertia, Newton's laws, friction, gravity, mass, weight, and terminal velocity.

What is a force?

A push, pull, or twist; an interaction between two objects.

What can a force do to the motion of an object?

It can accelerate, decelerate, or change the object's direction.

How are forces measured and what unit is used?

Measured with a spring balance; the unit of force is the Newton (N).

How do scientists represent forces graphically?

Using arrows; the direction shows the force direction and the length indicates its magnitude.

What is inertia?

The tendency of an object to resist changes in its motion; an object at rest stays at rest unless acted on by an unbalanced force.

What is Newton's first law of motion?

An object at rest stays at rest and an object in motion stays in motion unless acted on by an unbalanced force.

What is friction and what are its effects?

A force that opposes motion; it can be a contact force or, in some cases, a non-contact form like air resistance, and it slows moving objects.

What is traction and why is it useful?

Useful friction that provides grip, helping us move forward.

What is produced by friction that is usually unwanted?

Heat.

What is gravity?

The force of attraction toward the Earth; a non-contact force within Earth’s gravitational field.

What is mass?

The amount of matter in an object; measured in grams, kilograms, or tonnes; mass does not change.

What is weight?

The pulling force of gravity on mass; depends on mass and the planet's gravity; measured in Newtons (N).

What is terminal velocity?

The constant speed reached when weight is balanced by air resistance, so the object stops accelerating.

Is gravity a non-contact or a contact force?

Non-contact force; it acts at a distance within Earth's gravitational field.

How do mass and weight differ?

Mass is the amount of matter in an object; weight is the gravitational force acting on that mass.