Batteries and Bulbs

Batteries and Bulbs

Discover and Record how a battery can be used to light a bulb.

Two students, Wayne and Bill were discussing a recent flashlight purchase. “I love the Mag-Lite flashlights and last night I purchased one,” said Wayne. “I couldn’t decide whether to buy the one that uses two D-cell batteries or the one that uses two C-cells. I chose the one that uses C-cells because I noticed that the batteries only cost 75 cents while the D-cells were one dollar a piece,”

“That was silly,” said Bill, “The D-Cells are so much bigger and so that flashlight would be so much brighter. You’ll pay less for the batteries but the light will be so much dimmer than if you used D-cells.”

“I think the different batteries would create equal brightness in the bulbs,” says Wayne, “all of the batteries say 1.5 V on the side. Shouldn’t they be the same brightness if they have the same number on the side?”

Which student do you think is making the most sense? Bill who says the D-cell batteries will make the bulb shine brighter, or Wayne who thinks they will have the same brightness? Support your answer.

D-cell vs C-cell Batteries

Does the C or the D cell cause a single light to be lit brighter?

Can either cell light more than one bulb?

In what ways are the cells different? In what ways are they the same?

What about combining batteries

ShortCircuit

Never let a conductor touch both terminal leads

Be sure there is at least one bulb between the terminals

What is it about the battery that allows only a certain number of bulbs to be lit?

D-Cell

C-Cell

In what ways are the two cells different?

C vs D cell Power

Work Done by C and D Cells

What about

AA-cells

and

AAA-cells?

Power for AA vs AAA

Work Done by AA vs AAA

D-CellC-Cell

AA

-Cell

AA

A-C

ell

So What’s the Dif?

Two students, Wayne and Bill were discussing a recent flashlight purchase. “I love the Mag-Lite flashlights and last night I purchased one,” said Wayne. “I couldn’t decide whether to buy the one that uses two D-cell batteries or the one that uses two C-cells. I chose the one that uses C-cells because I noticed that the batteries only cost 75 cents while the D-cells were one dollar a piece,”

“That was silly,” said Bill, “The D-Cells are so much bigger and so that flashlight would be so much brighter. You’ll pay less for the batteries but the light will be so much dimmer than if you used D-cells.”

“I think the different batteries would create equal brightness in the bulbs,” says Wayne, “all of the batteries say 1.5 V on the side. Shouldn’t they be the same brightness if they have the same number on the side?”

Which student do you think is making the most sense? Bill who says the D-cell batteries will make the bulb shine brighter, or Wayne who thinks they will have the same brightness? Support your answer.

D-cell vs C-cell Batteries

Type of

Battery

Cost of Battery

Energy Provide

d(Joules)

Energy Provide

d(W-h)

Energy Provide

d(kWh)

Cost per kWh

D cell $1.58 61,776 17.160.0171

6$92.07

C cell $1.50 32,033 8.8980.0089

8$167.0

4

AA cell $0.58 9,270 2.5750.0025

75$225.2

4

AAA cell

$0.71 3,271 0.90850.0009

085$781.5

1

$0.07065

7 ¢ per kWh!

How much does it cost to toast a bagel?

Typical Toaster Power = 1,000 WattsTime = 3min = 180 sec

Energy = Power x Time = 180,000 Joules = 0.05 kwH

Com Ed rate 7¢ / kWhCost = 0.05kWh x (7¢ /

kWh)

Cost = 0.35¢

How much does it cost to toast a bagel?

0.35¢ = $0.0035

3 x $1.58 = $4.74

6 x $1.50 = $9.00

20 x $0.58 = $11.60

39 x $0.71 = $27.69