EM WAVES/LIGHT
What "waves" in a light wave?
The electric and magnetic fields oscillate.
What happens to parallel rays on a concave mirror?
They converge at the focal point.
What changes when light refracts?
Direction and wavelength change; frequency stays the same.
What kind of image does a convex lens form beyond 2f?
Real, inverted, and smaller
What never changes during refraction?
Frequency
Are EM waves transverse, longitudinal, or torsional?
Transverse
State the law of reflection.
Angle of incidence = angle of reflection
Formula to find speed in a medium with index n?
v= c/n
What is the lens formula?
1/f=1/do+1/di
Describe the image in a convex mirror (3 words)
Virtual, upright, smaller.
How do light and sound waves differ?
Light is transverse and doesn’t need a medium; sound is longitudinal and requires a medium.
What does a negative image distance mean?
The image is virtual and located behind the mirror.
What happens to wavelength in a denser medium?
It decreases.
How does magnification relate to image height?
m=hi/ho=-di/do
What happens when object is at focal point of a converging lens?
No image is formed (image at infinity)
What equation relates speed, frequency, and wavelength?
(speed = frequency × wavelength)
How does the image change as the object moves toward the focal point?
It becomes larger, upright, and virtual when inside the focal length.
What is the critical angle for diamond into air?
Approximately 24.4°.
What if a lens is in a medium with the same index?
The lens has no focusing power; light passes straight.
What is total internal reflection and when does it happen?
It's when all light reflects inside the medium; occurs when angle > critical angle.
List all types of EM waves in order of increasing frequency.
Radio, microwave, infrared, visible, ultraviolet, X-rays, gamma rays.
What image is always formed by a convex mirror?
Virtual, upright, and smaller
What happens at or beyond the critical angle?
Total internal reflection occurs.
What image does a diverging lens always form?
Virtual, upright, and smaller.
What determines final image size in a lens system?
The product of all lens magnifications