1. A swimmer climbs out of a swimming
pool on a warm, dry day. Almost immediately he begins
to feel cold.
Why is this?
A The water allows a convection current to remove heat from
his skin.
B The water takes latent heat from his body in order to
evaporate.
C The water on his skin is a good conductor of heat.
D The water prevents infra-red radiation
from reaching his body.
2. A substance consists of particles that are
close together and moving past each other at
random. The average
speed of the particles is gradually increasing.
What best describes the
substance?
A a liquid being boiled to form a gas
B a liquid being heated
C a solid being heated
D a
solid being melted to form a liquid
3. In a
hydroelectric power station, water from a reservoir falls down a long pipe
before entering
The turbines. The turbines then turn the
generator.
What is the overall
energy conversion?
A electrical energy into kinetic energy
B electrical energy into potential energy
C kinetic energy into chemical energy
D potential
energy into electrical energy
4. Some of the more
energetic molecules in a liquid leave the surface, leaving the rest of the
Liquid slightly cooler.
What is the name given to
this process?
A boiling
B condensation
C evaporation
D freezing
5. When we
talk about angles of incidence and reflection, we often talk about the normal.
The normal to a surface is an imaginary line that is perpendicular to the
surface. The normal line starts where the incident ray strikes the mirror. A
normal line is drawn for you in the sample problem above.
a. Draw a diagram that shows a mirror with a normal line and a ray
of light hitting the mirror at an angle of incidence of 60 degrees.
b. In the diagram above, label the angle of reflection. How many
degrees is this angle of reflection?
6. Light strikes a mirror’s surface at 20 degrees to the
normal. What will the angle of reflection be?
23.1
7. A ray of light strikes a mirror. The angle formed by
the incident ray and the reflected ray measures 90 degrees. What are the
measurements of the angle of incidence and the angle of reflection?
8. In a game of basketball, the ball is bounced (with no
spin) toward a player at an angle of 40 degrees to the normal. What will the
angle of reflection be? Draw a diagram that shows this play. Label the angles
of incidence and reflection and the normal.
Use a protractor to figure out the
angles of incidence and reflection for the following problems.
