Physics Review

Flashcards from lecture notes

For a system in simple harmonic motion, which of the following is the time required to complete a cycle of motion?

period.

If wavelength is kept constant, which increases as the speed of a wave increases?

frequency.

For a system in simple harmonic motion, which of the following is the time required to complete a cycle of motion?

period.

If wavelength is kept constant, which increases as the speed of a wave increases?

frequency.

Which term describes a material that does not allow light to be transmitted?

Opaque material.

Two mechanical waves that have positive displacements from the equilibrium position meet and coincide. What kind of interference occurs?

Constructive

When a light ray passes from water (n =1.333) into diamond (n = 2.419) at an angle of 45°, its path is

bent towards the normal

Waves arriving at a fixed boundary are

reflected and inverted.

How many nodes and antinodes are shown in the standing wave above?

five nodes and four antinodes

A light beam of light passes from zircon (n=1.923) into air (n=1.0003) at the angle of 60 degree, its path is

not bent, total internal reflection

A train moves down the track toward an observer. The sound from the train, as heard by the observer, is ____ the sound heard by a passenger on the train.

higher in pitch than

Which portion of the electromagnetic spectrum is used in cell phone communication?

microwaves

The farther light is from a source,

the more spread out light becomes.

An uneven finish surface provides a ____ surface for ____ reflection.

rough, diffused

When a straight line is drawn perpendicular to a flat mirror at the point where an incoming ray strikes the mirror’s surface, the angles of incidence and reflection are measured from the normal and

the angles of incidence and reflection are equal.

The image of an object in a flat mirror is always

the same size as the object.

In an electric circuit, charged particles do the following

a.

flow around in a closed loop.

b.

flow from higher potential to lower potential.

c.

get energy from an electron source.

d.

all the above

What type of mirror is used whenever a magnified image of an object is needed?

concave mirror

When red light and green light shine on the same place on a piece of white paper, the spot appears to be

yellow.

Which of the following situations is not true for magnets?

Unlike poles repel each other.

A microscopic magnetic region composed of a group of atoms whose magnetic fields are aligned in a common direction is called a(n) ____. In most materials, when these groups are randomly distributed, the substance will show ____ magnetism.

domain; no

A current can be induced in a closed circuit without the use of a battery or an electrical power supply by moving the circuit through a

magnetic field.

A 10.0 Ω resistor and a 50.0 Ω resistor are connected in series across a battery. If the current is 3.00 A, what is the voltage of the battery?

180 V

An electric current that changes directions at regular intervals is called

alternating current.

How does an electromagnetic wave propagate itself? Which following statement is incorrect?

The electromagnetic wave propagates faster than speed of light.

All of the following statements about the electromagnetic force are true except which one?

It exerts a force on either charged or uncharged particles.

What phenomenon is created by two tuning forks side by side that emit frequencies that differ by only a small amount?

beats.

When a light ray passes from water (n = 1.333) into diamond (n = 2.419) at an angle of 45°, its path is

bent toward the normal.

When electrons move through a metal conductor,

they move in zigzag patterns because of repeated collisions with the vibrating metal atoms.

If the batteries in a portable CD player provide a terminal voltage of 12 V, what is the potential difference across the entire CD player?

12 V

A current-carrying conductor in and perpendicular to a magnetic field experiences a force that is

perpendicular to the current.

Which of the following features of a given pendulum changes when the pendulum is moved from Earth’s surface to the moon?

the restoring force

What is the frequency of an electromagnetic wave with a wavelength of 1.0 x 10⁵m?

3.0 x 10³ Hz

What is the wavelength of an infrared wave with a frequency of 4.2 x 10¹⁴ Hz?

7.1x 10^-7 m

If a light ray strikes a flat mirror at an angle of 30° from the normal, the ray will be reflected at an angle of

60° from the mirror’s surface.

A pendulum clock is taken to the moon (g = 1.6 m/s²). How long must the pendulum be in order for the clock to continue keeping accurate time (1 second/cycle)?

0.041m

A ray of light in air is incident on an air-to-glass boundary at an angle of exactly 30.0° with the normal. If the index of refraction of the glass is 1.65, what is the angle of the refracted ray within the glass with respect to the normal?

18.0

Greenhouse gases like carbon dioxide and methane differ from atmospheric gases like oxygen and nitrogen because

greenhouse gases absorb and then reradiate low frequency infrared radiation.

If a 75 W lightbulb operates at a voltage of 120 V, what is the current in the bulb?

0.62 A

The resistanece of a conductor can be determiend if _____________are known.

potential difference and current

Part of a pencil that is placed in a glass of water appears bent in relation to the part of the pencil that extends out of the water. What is this phenomenon called?

refraction

A convex lens is

converging and used for magnifying glasses

The ____ of light can change when light is refracted because the medium changes.

wavelength

When light passes at an angle to the normal from one material into another material in which its speed is higher,

it is bent away from the normal to the surface.

When light passes at an angle to the normal from one material into another material in which its speed is lower,

it is bent toward the normal to the surface.

What type of image does a converging lens produce?

real or virtual

Which of the following describes what will happen to a light ray incident on a glass-to-air boundary at greater than the critical angle?

total internal reflection

An attracting force occurs between two charged objects when the charges are of

unlike signs.

Electric charge is

conserved.

The process of charging a conductor by bringing it near another charged object and then grounding the conductor is called

induction.

The figure shown above demonstrates charging by

induction.

If a lamp is measured to have resistance of 45 Ohms when it operates at a power of 80 W, what is the current through the lamp?

1.3 A

Where is the electric field of an isolated, uniformly charged, hollow metallic sphere greatest?

at the sphere’s outer surface

A conductor that is in electrostatic equilibrium has an electric field inside the conductor that

is zero.

For a conductor that is in electrostatic equilibrium, any excess charge

resides entirely on the conductor’s outer surface.

Which conversion process is the basic function of the electric motor?

electrical energy to mechanical energy

Which of the following wires would have the greatest resistance?

an aluminum wire 10 cm in length and 3 cm in diameter

Which of the following wires would have the least resistance?

an aluminum wire 40 cm in diameter at 40°C

If the potential difference across the bulb in a camping lantern is 9.0 V, what is the potential difference across the battery used to power it?

9.0 V

What is the path of an electron moving perpendicular to a uniform magnetic field?

circle

How much does it cost to operate a 695 W heater for exactly 30.0 min if electrical energy costs $0.060 per kW·h?

$0.02

A blow dryer draws 11 A when it is connected to 125 V. If electrical energy costs $0.090/kW·h, what is the cost of using the blow dryer for exactly 15 min?

$0.032

Three resistors with values of 3.0 Ω, 6.0 Ω, and 12 Ω are connected in parallel. What is the equivalent resistance of this combination?

1.7 Ω

What is the wavelength of microwaves of 3.0 x 10⁹ Hz frequency?

0.10 m

A flashlight bulb with a potential difference of 4.5 V across it has a resistance of 8.0 ohm. How much current is in the bulb filament?

0.56 A

A color TV draws about 2.5 A when it is connected to a 120 V outlet. Assuming electrical energy costs $0.060 per kW·h, what is the cost of running the TV for exactly 8 h?

$0.14

The following three appliances are connected in parallel to a 120 V house circuit: a toaster, 1260 W; a coffee pot, 740 W; and a microwave, 550 W. If all were operated at the same time, what total current would they draw?

21 A

Consider a thundercloud that has an electric charge of 10.0 C near the top of the cloud and -20.0 C near the bottom of the cloud. These charges are separated by about 1.0 km. What is the magnitude of the electric force between these two sets of charges? (k_c= 8.99 x10⁹ N·m²/C²)

1.8 x10⁶ N

A tuning fork with a frequency of 337 Hz what will be its wavelength at 10°C? [v = 331 m/s + (0.6 m/s/°C)•T]

1.0 m

When red light is compared with violet light in vacuum,

both travel at the same speed.

The superposition of mechanical waves can be observed in the movement of

water waves in a ripple tank.

Which of the following types of interference will occur when the pulses in the figure above meet?

complete destructive interference

In a permanent magnet,

domain alignment persists after the external magnetic field is removed.

A current in a long, straight wire produces a magnetic field. These magnetic field lines

form circles that go around the wire.

In soft magnetic materials such as iron, what happens when an external magnetic field is removed?

The material returns to an unmagnetized state.

When a light ray moves from air into glass, which has a higher index of refraction, its path is

bent toward the normal.

The power ratings on lightbulbs are measures of the

rate that they give off heat and light.

What is the frequency of infrared light of 1.0 x 10^-4 m wavelength?

3.0 x 10¹² Hz

If a force of 30 N streches a spring 0.2m, what is the spring constant?

+150 N/m