Fundamentals of Light
Practice Test
1.
A(n) __________, like the Moon, reflects light.
a.
illuminated body
b.
radiating body
c.
reflecting body
d.
laminated body
Hint
2.
How do the frequencies of red and violet light compare?
a.
Violet is shorter.
b.
They are identical.
c.
Violet is higher.
d.
They cancel each other out.
Hint
3.
The speed of a wave depends on the __________.
a.
energy
b.
medium
c.
amplitude
d.
frequency
Hint
4.
Heat is transferred by __________ when objects touch.
a.
thermoduction
b.
convection
c.
conduction
d.
radiation
Hint
5.
__________ is the point of the largest displacement where two waves meet.
a.
A crest
b.
A node
c.
An antinode
d.
A period
Hint
6.
Acceleration describes a change in __________.
a.
mass
b.
velocity
c.
momentum
d.
gravity
Hint
7.
The
a-t
graph corresponding to the
v-t
graph in Figure 3-10a would be ___.
a.
A straight horizontal line above the
t
axis
b.
A straight vertical line
c.
A line beginning at the origin with increasing positive slope
d.
A straight line with a constant positive slope
Hint
8.
A perpetual motion machine violates which law?
a.
first law of gravity
b.
third law of thermodynamics
c.
third law of conservation
d.
first law of thermodynamics
Hint
9.
What did Roemer prove?
a.
light has no speed
b.
light travels instantaneously
c.
light travels at a finite speed
d.
the correct speed of light
Hint
10.
The slope of the line tangent to the curve on a velocity-time graph at a specific instant of time is the __________.
a.
instantaneous velocity
b.
displacement
c.
average velocity
d.
instantaneous acceleration
Hint
11.
A 475-N trunk is resting on a plane inclined 40.0° above the horizontal. Find the components of the weight force parallel and perpendicular to the plane.
a.
F
g
x
= -305 N,
F
g
y
= -364 N
b.
F
g
x
= -364 N,
F
g
y
= -305 N
c.
F
g
x
= 364 N,
F
g
y
= 305 N
d.
F
g
x
= 305 N,
F
g
y
= 364 N
Hint
12.
The formula
represents the period of a pendulum, T. What is the period of a 3.5 m-long pendulum on Earth?
a.
1.4 s
b.
3.8 s
c.
3.2 s
d.
4.6 s
Hint
13.
In Figure 12-19, if you doubled the amount of zinc put into the beaker, which of the following effects would it have on the final equilibrium temperature?
a.
The final equilibrium temperature of the water and zinc would be lower.
b.
This question can not be answered without knowing the size of the container.
c.
It would have no effect; the final equilibrium temperature would be the same as before.
d.
The final equilibrium temperature of the water and zinc would be greater.
Hint
14.
How long will it take an airplane at rest that accelerates uniformly at 2.5 m/s
2
to reach a ground velocity of 7.0×10
1
m/s that is required for take off?
a.
4 s
b.
28 s
c.
11 s
d.
35 s
Hint
15.
If in Figure 5-13 the skier has mass 45 kg and the slope is at 35°, what is the component of the skier's weight parallel to the slope?
a.
440 N
b.
360 N
c.
250 N
d.
it cannot be determined with the given information
Hint
16.
Friction that you feel when you rub your hands together was changed from __________ to heat.
a.
kinetic energy
b.
sound energy
c.
thermal energy
d.
nuclear energy
Hint
17.
In Figure 14-2, if the scale of the graph is 1 block = 10 N on the vertical axis and one block = 2 cm on the horizontal axis, what is the spring constant?
a.
5 N/m
b.
500 N/m
c.
250 N/m
d.
20 N/m
Hint
18.
A wave that reflects off a flat surface will reflect at __________.
a.
a different angle from which it struck the surface
b.
the same angle at which it struck the surface
c.
a right angle to the surface
d.
an angle of zero
Hint
19.
Red and blue light make __________.
a.
magenta
b.
violet
c.
purple
d.
indigo
Hint
20.
A trough is __________ of a wave.
a.
the high point
b.
the midpoint
c.
the low point
d.
the starting point
Hint
