Physics Review

What is the difference between the pressures inside and outside a bicycle tire called?

Gauge Pressure

A piece of wood is floating in a tub of water. A second piece of wood rest on top of the first piece; it does NOT touch the water. If the second piece is removed from the first and placed in the water, what happens to the water level in the tub?

The water level remains unchanged

A cube of wood is floating on water. A cube of iron is totally submerged in water. The cubes are equal in volume. Which cube has the greater buoyant force acting on it?

The cube of iron has the greater buoyant force acting on it

Water flows through a horizontal pipe. The diameter of the pipe at point B is larger than the diameter of the pipe at point A. Where is the speed of the water the greatest?

Speed is the greatest at point A

Water flows through a horizontal pipe. The diameter of the pipe at point B is larger than the diameter of the pipe at point A. Where is the water pressure the greatest?

Water pressure is the greatest at point B

Which of the three phases of matter has a fixed volume?

Liquid and Solid

Which of the following is considered a fluid

Gas and liquid

Which of the following is associated with the law of conservation of energy in fluids?

Bernoulli's principle

An ideal fluid flows at 12 m/s in a horizontal pipe. If the pipe widens to twice its original radius, what is the flow speed in the wider section?

3 m/s
AV=AV

If the density of gold is 19.3 x 103 kg/m3, what buoyant force does a 0.60 kg gold crown experience when it is immersed in water?

0.30 N

A circular window of 30 cm diameter in a submarine can withstand a maximum force of 5.20 x 105 N. What is the maximum depth in a lake to which the submarine can go without damaging the window?

750 M

Density is

Proportional to mass and inversely proportional to volume

What is the main purpose of the demonstration with a floating diet coke and a sinking regular coke

Archimedes Principle

What term denotes the time for one cycle of a periodic process?

Period

A mass on the end of a spring undergoes simple harmonic motion. At the instant when the mass is at its maximum displacement from equilibrium, what is its instantaneous velocity?

At maximum displacement, its instantaneous velocity is zero

The frequency of a wave increases. If the speed of the wave remains constant, what happens to the distance between successive crests?

The distance between successive crests decreases

What was the main purpose of the pendulum wave demo

That the length of string determines the period of a simple pendulum

Doubling only the amplitude of a vibrating mass and spring system produces what effect on the systems mechanical energy?

Increases the energy by a factor of four

A mass oscillates on the end of a spring, both on earth and on the moon. Where is the period the greatest?

Same on both earth and moon

A mass is attached to a vertical spring and bobs up and down between points A and B. Where is the mass located when its kinetic energy is a maximum

Midway between A and B

Two wave impulses pass each other on a string. The pulse traveling toward the right has positive amplitude, and the pulse traveling toward the left has an equal positive amplitude. What happens when they occupy the same of region of space at the same time

Constructive interference occurs

A standing wave is established on a string that is fixed at both ends. If the string is vibrating at its fundamental frequency, how is the length of the string related to the wavelength of the standing wave?

The length of the string is equal to one-half of the wavelength

Refraction is caused by:

different wave lengths

Which of the following statements are true?

The loudness of a sound is related to its amplitude

In general, sound is conducted fastest through:

Solids

In order to produce beats, the two sound waves should have:

Slightly different frequencies

A sound source approaches a stationary observer. The frequency heard by the observer is:

higher than the source

A flat metal washer is heated. As the washer's temperature increases, what happens to the hole in the center?

The hole in the center will expand

If the pressure acting on a given sample of an ideal gas at constant temperature is tripled, what happens to the volume of the gas?

The volume is reduced to one-third of its original value.

Which two temperatures changes are equivalent?

1 degree Celsius = 1 Kelvin

The number of molecules in one mole of a substance:

is the same for all substances

Both the pressure and volume of a given sample of an ideal gas double. This means that its temperature in Kelvin must:

quadruple

The average molecular kinetic energy of a gas can be determined by knowing only:

The temperature of the gas

Express your body temperature (98.6 degress Fahrenheit) in Celsius degrees.

37 degrees Celsius

A thermally isolated system consists of a hot piece of aluminum and a cold piece of copper. The alumiun and the copper are in thermal contact. The specific heat of aluminum is more than double that of copper. Which object experiences the greater amount of

Both experience the same magnitude of heat transfer

The amount of heat necessary to raise the temperature of 1 gram of water by 1 degree Celsius is referred to as the:

Calorie

It is a well-known fact that water has a higher specific heat capacity than iron. Now, consider equal masses of water and iron that are initially in thermal equilibrium. The same amount of heat, 30 calories, is added to each. Which statement is true?

They are no longer in thermal equilibrium, the iron is warmer

Phase changes occur:

as the temperature remains the same

By which primary heat transfer mechanism does one end of a steel rod become hot when the other end is placed in a flame?

conduction

Which of the following best explains why sweating is important to humans in maintaining suitable body temperature?

Evaporation of moisture from the skin extracts heat from the body.

Which of the following are possible statements of the second law of thermodynamics?

All carnot engines operating between the same two temperatures have the same efficiency, irrespective of the nature of the working substance.

How is the thermal efficiency of a heat engine defined?

The efficiency is defined as the ratio between the work performed and the heat input at the higher temperature

In order for the efficiency of a Carnot engine to reach 100%, what would the temperature of the cold reservoir have to be?

Absolute zero

Is it possible to transfer heat from a cold reservoir to a hot reservoir?

Yes, if work is done, this transfers process can take place.

The efficiency of a heat engine is defined as the ratio of

The work it does to the heat input at the high temperature

When water freezes, the entropy of the water

Decreases

A heat engine receives 7000 J of heat and loses 3000 J in each cycle. What is the efficiency?

57%

A positively charged rod is brought close to one end of an uncharged metal rod but does not actually touch it. What type of charge does the end of the metal rod closet to the positively charged rod acquire?

The end of the metal rod closet to the positively charged rod acquires a negative charge

Two charged objects are separated by some distance. The charge on the first object is greater than the charge on the second object. How does the force between two objects compare?

The charged objects exert electrostatic forces on each other that are equal in magnitude and opposite in direction.

Two charged objects separated by some distance attract each other. If the charges on both objects are tripled with no change in distance between them, what happens to the magnitude of the force between the objects?

The force between them increases by a factor of 9

Which of the following statements are true? electric field lines

Electric field lines near positive point charges radiate outward

Is it possible for the electric field between two positive charges to equal zero along the line joining the two charges?

Yes, regardless of the magnitude of the two charges

Sphere A carries a net positive charge, and sphere B is neutral. They are placed near each other on an insulated table. Sphere B is briefly touched with a wire that is grounded. Which statement is correct?

Sphere B is now negatively charged

A positive object touches a neutral electroscope and the leaves separate. Then a negative object is brought near the electroscope, but does not touch it. What happens to the leaves?

The move closer together

If the voltage across a circuit of constant resistance is doubled, how is the current in the circuit affected?

The current is doubled

A circuit maintains a constant resistance. If the current in the circuit is doubled, what is the effect on the power dissipated by the circuit?

The power dissipated is quadrupled

In the war of the currents when electrification first began which method did Nichola Tesla Support?

Alternating current

Consider two copper wires. One has twice the cross sectional area of the other. How do the resistances of these two wires compare?

The thicker wire has half the resistance of the thinner wire