Classical Mechanics and Newton's Laws of Motion

What does Classical Mechanics describe?

The relationship between the motion of objects in our everyday world and the forces acting on them.

When does Classical Mechanics not apply?

To very tiny objects (< atomic sizes) and objects moving near the speed of light.

What is a force?

A push or pull that is a vector quantity and may be a contact or field force.

What are the four fundamental forces?

Strong nuclear force, electromagnetic force, weak nuclear force, and gravity.

What is Newton's First Law?

An object at rest remains at rest and an object in motion continues with the same velocity unless acted upon by an external force.

What is inertia?

The tendency of an object to continue in its original motion.

How is mass defined in physics?

A measure of the resistance of an object to changes in its motion due to a force, expressed in kilograms (kg).

What does Newton's Second Law state?

The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

What is the SI unit of force?

Newton (N).

What is weight?

The magnitude of the gravitational force acting on an object of mass near the Earth's surface, calculated as w = mg.

What does Newton's Third Law state?

For every action, there is an equal and opposite reaction; forces between two objects are equal in magnitude and opposite in direction.

What is a free body diagram?

A diagram that shows all the forces acting on an object of interest.

What is equilibrium in physics?

A state where the net force acting on an object is zero, meaning the object is either at rest or moving with constant velocity.

What is the equation for net force?

ΣF = ma.

What is static friction?

The force that acts to keep an object at rest from moving, which increases with applied force until it reaches a maximum value.

What is kinetic friction?

The force that opposes the motion of an object that is already in motion, calculated as ƒk = µn.

What is terminal speed?

The constant speed of an object when the upward force of air resistance equals the downward force of gravity.

How do you solve problems involving connected objects?

Apply Newton's Laws separately to each object, noting that the acceleration and tension are the same for both.

What is the relationship between normal force and friction?

Friction is proportional to the normal force, and the coefficient of friction depends on the surfaces in contact.

What is the significance of the coordinate system in physics problems?

Choosing an appropriate coordinate system helps in resolving forces into components and applying equations correctly.

What happens when an object is in equilibrium?

The net force acting on the object is zero, and it can be at rest or moving with constant velocity.

What is the difference between action and reaction forces?

Action and reaction forces are equal in magnitude and opposite in direction, acting on different objects.

What is the role of air resistance in motion?

Air resistance acts as a force opposing the motion of an object, increasing with the object's speed.