Name the theory that has the Sun in the middle of the Solar System
Heliocentric
Name the theory that has the Earth in the middle of the Solar System
Geocentric
Which theory about the structure of the solar system is correct, the geocentric or heliocentric?
Heliocentric (sun in the middle)
What is the name of our galaxy?
The Milky Way
What is a collection of stars called?
A galaxy
How did Galileos observation of Jupiter provide evidence for the heliocentric model of the solar system?
He saw that it had moons orbiting it. This proved that not everything orbited the Earth.
How can you measure the focal length of a distant object using a lens?
Hold the lens in front of a screen (eg paper) and adjust it until an image is formed on the screen. The focal length is the distance from the lens to the image.
What is a real image?
An image that can be projected (displayed) on a screen.
What is the opposite of a real image?
A virtual image
What is a virtual image?
An image that cannot be projected (displayed) on a screen.
What affects the magnification of a converging lens?
The distance between the lens and the object.
The shape of the lens - the more curved it is, the higher the magnification.
What are the names of the two lenses in a refracting telescope?
objective lens,
eyepiece lens
What is refraction?
When a wave (like light) hits the boundary between two different materials at an angle
What do waves do?
Transfer energy and information without transferring matter
What do we call the distance between two peaks of a wave?
Wavelength
What do we call the number of cycles per second of a wave?
Frequency
What is the unit of frequency?
Hertz (Hz) it means cycles per second
What is meant by the amplitude of a wave?
Amplitude is measured from the middle of a wave to the top of a peak
What are the two basic types of waves?
longitudinal
transverse
Are sound waves longitudinal or transverse?
Longitudinal (the vibrations are in the direction of travel of the wave)
Are electromagnetic waves longitudinal or transverse?
Transverse (the vibrations are across the direction of travel of the wave)
Are seismic waves longitudinal or transverse?
They can be either transverse or longitudinal
Name some types of waves that telescopes can detect
Visible light
infrared
x-rays
ultraviolet
radio
microwaves
Why are large telescopes better at viewing distant stars?
They can gather more light from the dim distant stars
Which type of telescopes use visible light but not lenses?
Reflecting telescopes. (They use mirrors instead of lenses)