Science final 2026

What is the average speed of a car traveling 100 kilometers in 25 minutes?

s=d/t s=1000km/25m s=4 km/m

A racecar travels 2000 meters in 20 seconds. What is the racecar’s average speed?

s=d/t s=2000/20 s=100 m/s

A plane traveled for about 2.5 hours at a speed of 1200 km/hr. What distance did it travel?

d=s(t) d=1200 x 2.5 d=3000km

What makes an object a good reference point for describing motion?

Something that does not move in reference to the object you are measuring

What is the term used to describe speed in a given direction?

Velocity

What is the term used to describe the rate at which velocity changes?

Acceleration

When objects slow down, are they accelerating? Why or why not?

Yes, because a change in speed or direction is still an acceleration

Is a car driving at a constant speed of 10 km/hr accelerating? Why or why not?

No, because speed/direction are not changing

Law of inertia, an object in motion stays in motion, and an object at rest stays at rest unless acted upon by an outside force

Newton's First Law of Motion

The net force acting on an object is equal to its mass times acceleration

Newton’s Second Law of Motion

For every action, there is an equal and opposite reaction

Newton’s Third Law of Motion

Momentum remains constant if no external force acts upon it. Momentum stays the same before and after a collision

Law of Conservation of Momentum

What is the difference between a balanced and an unbalanced force?

Balanced Force=Net Force 0N

Unbalanced Force=Unequal force, causes movement

The force that resists the motion of one surface sliding over another

Sliding Friction

The force that prevents a stationary object from moving

Static Friction

Friction from fluids

Fluid Friction

a resistance to motion.

Inertia

The force of gravity on a person or object on the surface of a planet

weight

describes how much matter is in a given volume

mass

the ability to do work or cause change

energy

An energy that an object possesses due to motion

Kinetic Energy

The stored energy an object has due to its position

potential energy

Energy stored in an object due to a force that temporarily changes its shape

Elastic Energy

Energy released from the nucleus of atoms

Nuclear Energy

What materials are good conductors of electricity?

metals

Which are good insulators?

rubber, glass, and wood

An unbroken path through which electric charges can flow

electric circuit

What completes the path of a current in a circuit?

A closed conductive path

What determines the resistance of a wire?

length, material, diameter, temperature

What happens when more branches are added to a parallel circuit?

decrease in resistance, increase in total current

What happens when more branches are added to a series circuit?

it gets dimmer

Provide examples of insulators and conductors

Conductors=metals

Insulators=wood, glass, rubber, air

Energy is always ____ in a circuit.

conserved

Every magnet, regardless of its shape, has ______.

two magnetic poles

The motion of liquid ___ in Earth’s outer core creates a magnetic field.

iron

A _____ is a device that has a magnetized needle that can spin freely.

compass

What is the difference between the Earth's magnetic poles and geographic poles?

Geographic poles are fixed points at N/S where the axis of rotation meets the surface, while magnetic poles are shifting locations where the planet’s magnetic field lines are vertical. They are not at the same location.

What creates mechanical waves?

disturbance or vibration in a medium

What is a standing wave?

A wave pattern that remains in constant position. Its antinodes are the points of maximum amplitude that occur halfway between two nodes

How often a wave occurs is the wave’s _____.

frequency

How does a transverse wave move in a medium?

The medium moves at right angles to the direction the wave travels

Ocean waves are an example of ______.

surface waves

Reflection

When parallel rays hit a surface and reflect at the same angle

Refraction

When light rays enter a new medium (material) and the change in speed causes the rays to bend

Interference

The interaction between two waves that meet

Resonance

An increase in the amplitude of a vibration that occurs when external vibrations match an object’s natural frequency

The less energy a wave has, the smaller its _____.

amplitude

Energy can be neither destroyed nor _____.

created

Describe how sound waves move.

By vibrating particles in a medium

Explain how the Doppler effect works

The motion of the source causes the waves to either get closer together or spread apart. This makes things like a firetruck seem louder when approaching you, but quieter as it drives away. This is because the motion of the object causes the sound waves to compress as the object moves towards you and spread apart as it moves away from you.

Sound travels as a ________.

longitudinal wave

The ____ of sound depends on the temperature, elasticity, and density of the medium through which the sound travels through.

speed

What is the difference between how sound travels through a warm and cold temperatures?

Sound travels faster in warmer temperatures than in colder ones

Sound waves with frequencies above the normal range of human hearing

ultrasound

What property/properties of sound depend on the energy and intensity of the sound waves?

Loudness

What are electromagnetic waves?

An electromagnetic wave is a transverse wave made up of vibrating electric and magnetic fields that move through space or some medium at the speed of light

Light that causes an electron to move so much that it is knocked out of a metal

photoelectric effect

List a common use/example of each wave on the electromagnetic spectrum:

Radio: Broadcasting signals for radio programs

Microwave: cell phone communication and radar

Infrared: heat bulbs

Visible Light: light that you can see

Ultraviolet: radiation from the sun

X Rays: imaging of bones and teeth

Gamma Rays: cancer treatment and imaging

What does a thermogram record?

Images of infrared radiation emitted by an object

How does radar work?

Uses reflected microwaves to detect objects and measure their distance and speed

What is the difference between AM and FM radio waves?

AM stations use kilohertz (kHz) and FM stations megahertz (MHz)

A material that reflects or absorbs all the light that strikes it is ____.

opaque