Physics 2 Review

A circuit is made up of a battery and four resistors as shown in the diagram. What is the total resistance of the circuit?

• 0.09 ohms

• 0.46 ohms

• 1.00 ohms

• 11.00 ohms

Four everyday devices that work by interactions of electrical and magnetic field are motors, transformers, generators, and electromagnets. Which pair of objects involves conversions between electrical and mechanical energy?

• Motors and Transformers

• Electromagnets and generators

• Motors and generators

• Electromagnets and transformers

The 2nd law of thermodynamics states that for any isolated system, energy transfers will occur in a way that increases entropy over time. Which situation below is an example of the 2nd law in action? (assume all situations are isolated systems)

• If gases A and B are the same temperature as gas C, they are the same temperature as each other.

• A puddle of water evaporates into water vapor, even when it's cold.

• A heat engine is given 100 Joules of heat energy, and performs 100 Joules of work to move a piston.

• A substance at absolute zero has no energy, and molecular motion stops.

A scientist is trying to identify the elements in a gas by using a gas discharge tube and a spectroscope. The picture shows the emission spectrum he records when the gas is heated. The elements can be identified by the spectrum because-

• the distance between any pair of lines corresponds to a unique element

• the width of each line is characteristics of a unique element

• the location of a line on the spectrum corresponds to a unique element

• the brightness of any given line is characteristic of a unique element

The diagram shows the fusion reaction that takes place at the core of the Sun, producing energy. When 4.031 kg of hydrogen nuclei (H) fuse forming 4.003 kg of helium nuclei (He) and 0.001 kg of positrons (e+), what is the magnitude of the energy released?

• 0.027 J

• 4.004 J

• 2.430 x 10^15 J

• 3.604 x 10^17 J

Convection occurs

• only in gases and liquids

• only in liquids and solids

• only in liquids

• only in gases

A cart with a velocity of 5m/s has an inelastic collision with a stationary cart. The carts couple and stay attached. The masses of the carts are shown in the diagram. What is the final velocity of the two carts after the collision?

• 1 m/s

• 2 m/s

• 5 m/s

• 25 m/s

An object is placed 15 cm away from a convex lens of focal length 10 cm. How far is the image from the lens, and is the image real or virtual?

• 6 cm, real

• 6 cm, virtual

• 30 cm, real

• 30 cm, virtual

The illustration shows a longitudinal wave and a transverse wave. What is the major difference between the two types of waves?

• The particle displacement due to vibrations is different in all longitudinal and all transverse waves

• The wavelengths of all longitudinal waves are greater than the wavelengths of all transverse waves.

• The frequencies of all transverse waves are greater than the frequencies of all longitudinal waves.

• All transverse waves travel at the same speed, but all longitudinal waves travel at different speeds.

In which circuit does the ammeter (placed at point A) show the greatest current?

• A

• B

• C

• D