Regular Physics 2nd Semester Study Guide
Unit 9 (Thermodynamics)
1. Define
Heat Thermal energy, flows from higher temp to lower temp.
Temperature Average kinetic energy of particles
1st law of thermodynamic Change in internal energy is equal to the heat absorbed minus the work done by a system.
2nd law of thermodynamics Entropy always increases (not all heat can be converted to work)
0th law of thermodynamics Heat flows from higher temp to lower temp
adiabatic system No heat gained or lost. Q=0 so ΔU=W
2. How can a gas do work? What occurs when work is done on or by a gas? By expanding or contracting (remember work
equals force x distance. No movement means no work).
3. Describe entropy. How would an increase or decrease in entropy affect the arrangement of matter at the microscopic
level? Entropy is chaos, more spreading, less orderly configuration.
4. How are work and entropy related? Some energy to do work is always lost to entropy
5. 3450 J of heat are required to raise the temperature of a chunk of copper from 23.0°C to 315°C. What is the mass of
the copper? 0.0306-kg
6. An aluminum can of mass 0.200-kg at 25°C is placed in a cooler and allowed to cool to 10°C. How much heat was
removed from the can? 2700-J
7. In a ballistic pendulum experiment a bullet is shot into a 400-g piece of wood.
a. If the bullet has a mass of 3.50 g and a speed of 225 m/s and it stops when it hits the wood, what is the change in
kinetic energy of the bullet?88.6-J
b. If all that K.E. is converted to heat what is its final temperature when it comes to rest? (cwood = 7.33 J/kg°C)?30.2°C
Unit 10 (Harmonic Motion and Sound)
1. Define
amplitude displacement from equilibrium position
frequency times a revolution occurs in one second
period time to complete one revolution
intensity Power per unit area (loudness of a sound wave)
wavelength distance between successive identical points in a wave front.
loudness perception of intensity
2. Describe wave interference and the conditions that lead to constructive and destructive interference.
3. According to the Doppler Effect how will the perceived frequency of a siren differ from the source as it approaches an
observer? As it departs from an observer? Is related to frequency (not loudness). When distance between source an
observer is diminished the wave is squished increasing frequency.
4. Explain the differences between longitudinal and transverse waves.
5. What factors influence the speed of sound? Air temp, humidity, power of wave, density of medium
6. A sound wave has a wavelength of 0.75 m and a speed of 340 m/s. What is the wave frequency?
7. A sound wave has a frequency of 250-Hz and a speed of 340 m/s. What is the wavelength?
8. The speed of sound in air is 340 m/s, what frequency does an observer hear if…
a) the source frequency is 1200 Hz, and the observer is moving away from a stationary source at 34 m/s?
b) the source frequency is 1440 Hz, and the observer is moving toward a stationary source at 26 m/s?
c) the source frequency is 550 Hz, and the source is moving away from the stationary observer at 110 m/s?
*9. You are on a train traveling at 105 km/h. You approach a stationary 455 Hz siren. What is frequency you hear? (use
340 m/s for speed of sound)
*10. You are on a train traveling at 55.0 km/h. You approach a bell. You hear a frequency of 725 Hz. What is the actual
frequency of the bell?
Unit 11 (Light and Optics)
1. Define
refraction bending of light as it enters a new medium.
diffraction bending of light as it passes through a narrow opening
reflection the rebounding of light after colliding with a surface.
2. Understand Snell’s law, e.g. when a light ray passes from air (n = 1.0003) into plastic (n=1.36) at an angle of 40°, its
path is bent inward according to the equation n1sinθ1 = n2sinθ2. The light is forced to slow down, so it will bend in
toward the center line.
3. What type of image(s) are formed by convex and concave mirrors depending upon the orientation of mirror and
object? Convex mirrors always produce upright smaller images. Concave mirrors produce larger upright images up
close (inside the focal length) and smaller upside down images outside of the focal length. Outside of 2 times the focal length they produce larger upside down images.
4. What type of image(s) are formed by diverging and converging lenses depending upon the orientation of mirror and
object? Diverging lenses always produce upright smaller images. Converging lenses produce larger upright images up
close (inside the focal length) and smaller upside down images outside of the focal length. Outside of 2 times the focal length they produce larger upside down images.
5. Explain what a diffraction grating is, and how the variables (L, y, d and λ) are related to one another. A very narrow
series of lines that forces light interfere with itself after passing through. The pattern formed by this interference
looks like minute bright spots. The separation of these bright spots is represented by y. Increasing the distance to the
screen (L) increase y. Increasing the wavelength of light (λ) increases y. Increasing the distance between the narrow
lines (d) decrease y. The formula for all of this is
y=
6. A beam of light in air is incident at an angle of 35° to the surface of a rectangular block of clear plastic (n = 1.49). What
is the angle of refraction?
7. A laser is shone at an angle of 50° to the surface of a rectangular block of polyethylene and is refracted at an angle of
32°. What is the index of refraction for the polyethylene?
8. An object is placed along the principal axis of a thin converging lens that has a focal length of 19 cm. If the distance
from the object to the lens is 27 cm, what is the distance from the image to the lens?
*9. The distance between the two slits in a double-slit experiment is 0.04 mm. The second-order bright fringe (m = 2) is
measured on a screen at an angle of 2.2° from the central maximum. What is the wavelength of the light in nm?
*10. A red laser pointer has a wavelength of 669 nm. With the screen 1.00 m away, a double-slit apparatus shows a
first-order bright band at 64.3 mm. Calculate the distance in meters separating the two slits.
Unit 12 (Electrostatics)
1. Describe what occurs when an object becomes negatively charged. Gains electrons
2. Describe what occurs when an object becomes positively charged. Loses electrons
3. What is a capacitor, and how can it power electrical devices? A physical mechanism for storing charge. Two metal
plates are separated by a narrow gap. Opposite charge is accumulated on each plate by transferring electrons from
one to the other. To power a device the electrons go home.
4. What is Coulomb’s law? The force that exists between two charged objects is directly related to their charge and obeys
in inverse square law according to the distance between them.
Fe =k c
q1 q2
r2
5. Know what electric field lines look like between point charges with the same charge, and between point charges with
opposite charges.
6. If two positively charged spheres repel one another with a force of 0.25-N, what is the distance between them if they
each have a charge of +5.8 x 10-4C.
7. If a charged particle has a potential of 4800-V when it is located 2.0-m from the source of an electric field which has a
magnitude of 360-N/C, what is the voltage when the charged particle is 75-cm from the source?
8. A 0.45 μF capacitor is connected to a 12.0 V battery. What is the charge on the capacitor?
9. An object has a charge of -0.009C. How many excess electrons does it have?
*10. Find the distance between 2 positively charged spheres (+23μC) if the electrical force between them is 358 N.
Unit 13 (Electric Circuits)
1. What are the differences between a series and a parallel circuit? Series has only one path. Parallel has many. This leads
to other differences in terms of voltage and current.
2. What causes electrons to move in an electric circuit? An electric field of a certain strength per coulomb.
3. What factors affect the resistance of a wire? How would you select the one with the least resistance? With the most?
Temperature, length, width and the material itself. The least resistance would be the coldest, shortest, widest wire of a
particular material. The Most resistance would be the longest, hottest, and thinnest wire.
4. Define:
lightbulb Converts kinetic energy of electrons into light.
battery Converts chemical energy into electricity.
resistor Opposes the flow of electrons in a circuit.
capacitor Mechanical device for storing electric charge.
equivalent resistance The sum of the individual resistors in a circuit.
5. What is the resistance in an electrical device if 12 A of current flow through it when attached to a voltage of 220 V?
6. What is the equivalent resistance of a 240, 880Ω, and a 560Ω resistor connected in parallel?
7. What is the equivalent resistance of a 750Ω, 320Ω, and a 170Ω resistor connected in series?
10. How much does it cost to operate a 350 W heater for exactly 10.0-min if electrical energy costs $0.060 per kW•h?
Unit 14 (Magnetism)
1. Describe what occurs when a bar magnet is broken in half. You get two smaller complete magnets.
2. Know the right hand rule for current carrying wires AND moving electric charges.
3. Know the magnetic field lines around a bar magnet, and how a compass would point around the same.
4. Be able to explain an electric motor and an electric generator.
5. What factors can be changed (and how) to increase the EMF of an induction apparatus.
Use a stronger magnet, or move the magnet faster.
6. What is the root source of all magnetic phenomenon? Moving electric charges.
7. In a particle accelerator a positron (C= +1.6 x 10-19) travels through a perpendicular magnet field with a magnitude
of 3.1 x 10-2 T. At what speed must the positron travel in order for it to experience a force of 4.75 x 10-14 N?
8. An alpha particle (2 protons and 2 neutrons) experiences a downward force of 2.9 x 10-14 N while traveling in a
magnetic field with a strength of 5.1 x 10-19 T pointing to the north. Find the speed of the particle and the direction it
must be traveling in.
9. A magnetic force of 0.158 N is exerted upon a 0.068 m long wire. If the wire is carrying 15 amps of current, find the
strength of the magnetic field.
10. Find the length of a wire if it experiences a .63N force when it travels through a magnetic field with a strength of
0.85T whilst carrying 5.0 amps of current. (14 SG)
Unit 15 (Nuclear Physics)
1. What role do electrical forces play in nuclear stability? They only add to instability.
2. Describe the path of alpha and beta particles while travelling through a magnetic field. Opposite directions (they
have opposite charges, remember knuckles for negative and palm for positive)
3. Describe fission and fusion and give examples of where they occur in nature.
4. Where does the energy released in nuclear phenomenon originate?
5. What is half-life?
6. What is the origin of most of the radiation we are exposed to?
7. Calculate the binding energy of the carbon-14 nucleus. (c2 = 931.50 MeV/u; atomic masses:
= 1.007 825 u; mn = 1.008 665 u
8. A pure sample of U-235 contains 2.3 x 1014 atoms of the isotope. If there is a final amount remaining of 2.2 x 1014
atoms remaining after 24 years, what is the half-life of U-235?
(* indicates material not covered on the senior final)