MCQ: A sharp image is formed when light reflects from a(n) _____.
A) rough
B) smooth
C) absorbent
D) black
B) smooth
Complete:
The human eye has two .............lenses.
convex
Complete:
Sound travels faster in.............. than in liquids.
Solid
MCQ:
A red ball reflects which of the following colors of light?
A) red
B) all colors but red
C) green
D) white
A) Red
Complete :
The reflection of light waves from a rough surface is.......... reflection.
diffuse
MCQ: Which would cause light to bend the most after traveling through air?
Solids
liquid
gas
Solid
MCQ:
Waves that need to travel through matter are known as
Medium waves
Mechanical waves
Air waves
Heat waves
Mechanical waves
Complete:
A material used to make paints that reflects some colors of light and absorbs others is called
a(n)...................
Translucent
Give an example of a phenomenon that results in the scattering of light.
fog, clouds, dust in the air
Give an example of a device that uses a lens or lenses.
binoculars, eyeglasses, camera, magnifying glass
Complete :
A high point of a wave is known as a.................
Crest
there are 2 types of cells in the eye responsible for detecting different stimuli. clarify each and which stimulus they respond to?
Rod : detect shades
cone : colors
which Mirrors form virtual images?
Plane & convex
Your friend places a straw in a glass of water and is surprised to notice that the straw looks like it has broken at the surface of the water. Write an explanation to help your friend understand this phenomenon.
due to refraction. When light moves from one medium to another,
its speed changes. For example, when it moves from air to water, it slows down.
the distance between the first crest and the third crest is 20cm.calculate the wavelength
10cm
compare between Radio waves and X rays in 2 points
Radio waves : longest wavelength , lowest energy and frequency , used in communication
X-Rays: short wavelength , high frequency and energy , used in making images for teeth and bones
compare between concave and convex mirrors in 3 points?
Concave mirror
- The curved surface is inward
- It converges (get together) the light rays
- it forms real images
Convex mirror
- The curved surface is outward
- It diverges ( spread) the light rays
- it forms virtual images
Compare between convex and concave lens in 3 points
Concave :
Curve inward
Makes light diverge
Thicker at the edges than middle
Convex
Curve outward
Makes light converge
Thicker in the middle than edges
4
short wavelength will lead to high frequency
Describe the path of the waves in each of the following:
1. the interactions of a light wave with a piece of cardboard
2. the interactions of a sound wave with a piece of cardboard
Light waves and sound waves will reflect off a piece of cardboard.
Light waves and sound waves will be absorbed by a piece of cardboard.
A sound wave will transmit through a piece of cardboard, but a light wave will not.