Ohm's Law: Activity Sheet
Name______________________________________________________
Date_______________Period_______
As you move through the procedure record your observations here.
TABLE 1
| STEP |
GEL BOX CONTENTS |
POTENTIAL
(volts) |
CURRENT
(milliamps) |
OTHER OBSERVATIONS
(color changes, bubbles, etc.) |
| 2 |
Empty (air only inside) |
100 V |
|
|
| 4 |
Distilled water |
100 V |
|
|
| 6 |
Distilled H2O + 1 mL NaCl |
100 V |
|
|
| 8 |
Distilled H2O + 2 mL NaCl |
100 V |
|
|
Use the graph below to draw a bar graph using the information in steps 2, 4, 6,
and 8.
GRAPH 1
Current
in
milliamps
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Step 2 |
Step 4 |
Step 6 |
Step 8 |
|
- Remembering that the higher the resistance, the harder it is for electricity to flow, summarize in your own words the resistance of air, distilled water, and water
with NaCl.
Record data from Steps 6 (again) and 7 in the table below.
TABLE 2
| STEP |
GEL BOX CONTENTS |
POTENTIAL
(volts) |
CURRENT
(milliamps) |
OTHER OBSERVATIONS
(color changes, bubbles, etc.) |
| 6 |
Distilled H2O + 1 mL NaCl |
100 V |
|
|
| 7 |
Distilled H2O + 1 mL NaCl |
|
|
|
| 7 |
Distilled H2O + 1 mL NaCl |
|
|
|
| 7 |
Distilled H2O + 1 mL NaCl |
|
|
|
| 7 |
Distilled H2O + 1 mL NaCl |
|
|
|
| 7 |
Distilled H2O + 1 mL NaCl |
|
|
|
| 7 |
Distilled H2O + 1 mL NaCl |
|
|
|
| 7 |
Distilled H2O + 1 mL NaCl |
|
|
|
Use the graph below to plot the information in Steps 6 and 7.
GRAPH 2
- Summarize in your own words the relationship between potential and current.
Record data from Steps 4, 6 (again), 8, and 9 in the table below.
TABLE 3
| STEP |
GEL BOX CONTENTS |
POTENTIAL
(volts) |
CURRENT
(milliamps) |
OTHER OBSERVATIONS
(color changes, bubbles, etc.) |
| 4 |
Distilled H2O |
100 V |
|
|
| 6 |
Distilled H2O + 1 mL NaCl |
100 V |
|
|
| 8 |
Distilled H2O + 2 mL NaCl |
100 V |
|
|
| 9 |
Distilled H2O + 3 mL NaCl |
100 V |
|
|
| 9 |
Distilled H2O + 4 mL NaCl |
100 V |
|
|
| 9 |
Distilled H2O + 5 mL NaCl |
100 V |
|
|
| 9 |
Distilled H2O + 6 mL NaCl |
100 V |
|
|
| 10 |
Distilled H2O + 7 mL NaCl |
100 V |
|
|
Use the graph below to plot the data from steps 4, 6,8 and 9.
GRAPH 3
Current
in
milliamps
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| RESISTANCE (in mL of NaCl) |
|
- From the graphs below, select the graph which most looks like GRAPH 3 of your data.
 |
 |
| y = n (1/x) |
y = n x2 |
 |
 |
| y = n x |
y = - n x + 5 |
- Use this equation to figure out Ohm's Law. Substitute resistance (R) for the
variable "x". Substitute current (I) for the variable "y". The letter "n" is a
constant, which, in this case, be voltage (V). Write down the equation with the
substitutions. This is Ohm's Law.
- Using this equation, calculate the actual resistance in ohms (W) for each pair of voltage and current for the eight amounts of NaCl in Table 3. Don't forget to convert the milliamp readings into amps (for example, 80 milliamps
would be equal to 0.08 amps). Do your work on the back of this page, and list your
calculated results below. ( The list has been started for you.)
0 NaCl:
1 mL NaCl:
- What happens to the current if the resistance is increased in a circuit?
- What happens to the current if the resistance is decreased in a circuit?
- What are the two ways that one can decrease the current in a circuit? Use Ohm's
Law to explain.
- Use Ohm's Law to calculate the following. SHOW YOUR WORK! If V =50 volts,
and R = 5 W, what is the current?
- If I = 40 amps and R = 3
 , what is the voltage?
Overview
Procedure
|
|
|
AE Partners Collection Index
