Module 4 - EPR (Potential Dividers)

Question 1

Define Potential Divider

Answer 1

Multiple resistors in series that splits potential difference according to proportion

Question 2

What is the relationship between Resistance and Potential Difference

Answer 2

V α R, becauseas the opposition to the flow of charge increases the energy reuired to overcome this resistance per unit charge increases

Question 3

Give the 2 potential divider equations

Answer 3

1. V1/V2 = R1/R2
2. Vout = Vin x R2/ (R1+R2)

Question 4

Describe the affect on the Vout when
1. The Vin increases or decreases
2. The potential difference of the resistor not connected to Vout increases or decreases
3. The resistance of the resistor not connected to Vout increases or decreases

Answer 4

1. if Vin increases by factor 2 the Vout increases by a factor of 2. if Vin decreases by factor 2 the Vout decreases by a factor of 2
2. If the potential difference increases, due to Kirchhoff’s 2nd law and ε being constant if V of the 2nd resistor increases then V of the connected resistor and so Vout must decrease and vice versa
3. If the resistance increases, more energy is used up per unit charge therefore the potential difference increases, and so due to Kirchhoff’s 2nd law and ε being constant if V of the 2nd resistor increases then V of the connected resistor and so Vout must decrease and vice versa