https://phet.colorado.edu/sims/html/ohms-law/latest/ohms-law_en.html

1) Keep the default settings

A) What is the current when V = 4.5 V and R = 500 ? Answer: ________________________________________________________________________________

B) What does V on the left stand for? Answer: ________________________________________________________________________________

C) What does the V to the right of 4.5 stand for? Answer: ________________________________________________________________________________

D) What does R stand for? Answer: ________________________________________________________________________________

E) What does stand for? Answer: ________________________________________________________________________________

F) What is the symbol for intensity of current? Answer: ________________________________________________________________________________

G) What is the SI unit for current? What is the symbol for it? Answers: ________________________________________________________________________________

H) What does mA stand for? How many mAs is 1A? Answers: ________________________________________________________________________________

I) What is an Ampere in terms of Coulombs? Answer: ___________________________

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2) Keep default settings.

A) Double only the Voltage. What is the new Voltage with its unit? Answer: ________________________________________________________________________________

B) What is the new current, with unit, with this voltage if resistance stays constant? Answer: ________________________________________________________________________________

C) What is the relationship between V and I then? (Directly or inversely proportional) Answer: ________________________________________________________________________________

D) What shape would the curve of the I vs V graph be? Answer: ________________________________________________________________________________

3) Refresh to return to default settings.

A) Double only the resistance this time. What is the new R with its unit? Answer: ________________________________________________________________________________ Continued

B) What is the current, if the voltage stays constant? Did it double, halve, or stay the same compared to 1A? Answers: ______________________________________________________________________________

C) What is the relationship between R and I then? (Directly or inversely proportional) Answer: ________________________________________________________________________________

D) What shape would the curve of the I vs R graph be? Answer: ________________________________________________________________________________

E) Refresh to default settings, Double both the resistance and Voltage. What is the current now? Did it double, halve, or stay the same compared to 1A? Why? Answers: ________________________________________________________________________________

4) Refresh the sim.

A) Change the Voltage to 0.1 V, what does the R have to be to make the current 1.0 mA? Answer: ________________________________________________________________________________

B) If 1.0 mA passes through your heart for a second or so, could it be fatal? Answer: ________________________________________________________________________________

C) Now, keep the R as in 4B and change the V to 9V. What is the new current? Answer: ________________________________________________________________________________

D) If the current in 4C passes through your heart for 2 seconds, could it be fatal? Answer: ________________________________________________________________________________

Resistance in a Wire

https://phet.colorado.edu/sims/html/resistance-in-a-wire/latest/resistance-in-a-wire_en.html

5) Keep the default settings.

A) What happens to R when resistivity, , increases? (Increases, decreases or stays the same) Answer: ________________________________________________________________________________

B) What is the relationship between and R, then? (Directly or inversely proportional) Answer: ________________________________________________________________________________

C) What happens to R when length, L, increases? (Increases, decreases or stays the same) Answer: ________________________________________________________________________________

D) What is the relationship between L and R, then? (Directly or inversely proportional) Answer: ________________________________________________________________________________

E) What happens to R when the cross-sectional Area, A, (based on the radius of the cylindrical wire) increases? (Increases, decreases or stays the same) Answer: ________________________________________________________________________________

F) What is the relationship between A and , then? (Directly or inversely proportional) Answer: _____________________________________________________________________