julie

1. If the average family washes 300 loads of laundry per year, and traditional washing machines use 100 Liters more water per load than water efficient machines, how many liters would an effecient washing machine save per year?

2. If the average cost of water in the United States is .50 cents for every 1,000 liters, how much money would you save annually by using the more efficient washing machine?

3. Given your calculated annual savings, how many years would it take for your water savings to pay for the more expensive, high efficiency washer?

Suppose you move into a new house and need to purchase a washing machine. You've heard that the new front-loading machines use less water, but that they are more expensive. A traditional washing machine costs $300, whereas the water efficient washing machines cost $900. So how do you choose?

1. If the average family washes 300 loads of laundry per year, and traditional washing machines use 100 Liters more water per load than water efficient machines, how many liters would an effecient washing machine save per year?

2. If the average cost of water in the United States is .50 cents for every 1,000 liters, how much money would you save annually by using the more efficient washing machine?

3. Given your calculated annual savings, how many years would it take for your water savings to pay for the more expensive, high efficiency washer?

Suppose you move into a new house and need to purchase a washing machine. You've heard that the new front-loading machines use less water, but that they are more expensive. A traditional washing machine costs $300, whereas the water efficient washing machines cost $900. So how do you choose?

1. If the average family washes 300 loads of laundry per year, and traditional washing machines use 100 Liters more water per load than water efficient machines, how many liters would an effecient washing machine save per year?

2. If the average cost of water in the United States is .50 cents for every 1,000 liters, how much money would you save annually by using the more efficient washing machine?

3. Given your calculated annual savings, how many years would it take for your water savings to pay for the more expensive, high efficiency washer?

CO2

B 

CH4

C 

Br2

D 

NH3

H2O

B 

NH3

C 

CCl4

D 

KCl

2-6

B

2-8

C

2-8-6

D

2-8-8

noble gas configuration.

B

halogen gas configuration.

C

low ionization energy configuration.

D

high electronegativity configuration.

a) to suggest that their friendship was less significant than other events

B

to show that the friendship was not as interesting to Emma as she hoped

C

to demonstrate that their new friendship developed easily and quickly

D

to emphasize that their friendship grew over a long period of time

a)  the long-standing rancor that exists between him and Emma's family

B 

the significance of the threat he poses to Emma's aspirations

C 

the dishonesty of his actions toward Harriet

D 

the unsuitability of a match between him and Harriet

Two circuits are created using two identical light bulbs. In the circuit A, the bulbs are hooked up in series. In circuit B, the light bulbs are hooked up parallel. Each circuit is powered by a 6-volt battery.

Which statement or observation would not be supported by the two circuits?

a) The current in the circuit A would be less.

b) The light bulbs in the circuit B would be brighter

c) The light bulbs in circuit B are equal in brightness.

d) If one light burns out in circuit A, the other bulbs gets brighter.

A lamp is plugged into a standard 120-volt outlet. If the lamp draws a current of 0.5-amps, how much energy is consumed in 1 minute?

a) 3600 j

b) 2400 j

c) 600 j

d) 300 j

A 9V battery is directly connected to each of 3 LED bulbs. Select the statement that accurately describes this circuit.

A) A direct current is flowing through the bulbs using a series circuit so each bulb has the same current.

B) A direct current is flowing through the bulbs using a parallel circuit so each bulb has the same voltage.

C) An alternating current is flowing through the bulbs using a parallel circuit so each bulb has the same current.

D) An alternating current is flowing through the bulbs using a series circuit so each bulb has the same voltage.

Which of the following is a reasonable method to investigate magnetic poles to determine the flow of electrons?

a)Momentarily pass an electrical current through an iron nail. Then hold the nail beside a compass to determine the North and South poles of the temporary magnet you created.

b)Take a long piece of wire and wrap it around an aluminum bar. Connect the two ends of the wire to a battery and let it run for a few moments. Then place the magnet near the aluminum bar.

c)Continuously rub two iron nails against each other for a few moments. Then hold one nail beside a compass todetermine the North and South poles of the temporary magnet you created.

d)Suspend a bar magnet from a string attached to a ring stand. Place a paperclip hanging from the magnet. Without touching the paperclip, slowly insert a piece of aluminum foil between the paperclip and magnet to see if the paperclip falls off.

If the resistance of a circuit is reduced by one-half (1/2) and the current remains the same, what happens to the voltage?

a) it will increase by a factor of four

b) it will increase by a factor of two

c) it will decrease by one fourth

d) it will decrease by one half

A student wraps a copper wire around a nail and then connects the wire to a battery.Which statement describes the role of the nail in this set-up?

The nail is an electromagnet. The current in the wire induces a magnetic field from the nail.

The nail is a permanent magnet. The current in the wire induces a magnetic field from the nail.

The nail is an electromagnet. The magnetic field from the nail induces an electric current in the wire.

The nail is a permanent magnet. The magnetic field from the nail induces an electric current in the wire.

Wrapping the wire around the core more times so that it is longer.

Using a core like aluminum so that the magnet does not weigh much.

Using a very thin core so that it does not take much wire to wrap around it.

Wrapping the wire in both directions around the core so that electricity can flow longer

A

resonance.

B

diffraction.

C

reflection.

D

refraction.

A) Send pulses down a slinky at a variety of wavelengths and measure the reflected amplitudes.

B) Strike tuning forks of various frequencies and observe the beat frequencies that are created

.

C) Shine lasers of various colors at a narrow slit in an index card and measure the distance between the bright spots.

D) Emit sound waves from a car moving at a variety of speeds and listen to the pitch of the sound as it moves towards and past.

Several natural events, such as the blue color of the sky, can be explained by the scattering of light. Which statement is generally true about the scattering of light?

A) Larger particles scatter light of shorter wavelengths.

B) Smaller particles scatter light of shorter wavelengths.

C) Scattering of light is independent of the size of particles.

D) Scattering of light is independent of the wavelength of light.