If a potentiometer is used to measure the EMF of a cell and the balance point is
Practice Questions
Q1
If a potentiometer is used to measure the EMF of a cell and the balance point is found at 3 m, what can be inferred about the cell's EMF if the potential gradient is 1.5 V/m?
1.5 V
3 V
4.5 V
6 V
Questions & Step-by-Step Solutions
If a potentiometer is used to measure the EMF of a cell and the balance point is found at 3 m, what can be inferred about the cell's EMF if the potential gradient is 1.5 V/m?
Correct Answer: 4.5 V
Step 1: Understand that the EMF (Electromotive Force) of a cell can be calculated using the formula: EMF = potential gradient × length.
Step 2: Identify the values given in the question. The potential gradient is 1.5 V/m and the length at which the balance point is found is 3 m.
Step 3: Substitute the values into the formula. EMF = 1.5 V/m × 3 m.
Step 4: Perform the multiplication. 1.5 multiplied by 3 equals 4.5.
Step 5: Conclude that the EMF of the cell is 4.5 V.
Potentiometer – A device used to measure the electromotive force (EMF) of a cell by balancing it against a known potential gradient.
Potential Gradient – The change in electric potential per unit length, which is used to determine the EMF when multiplied by the length at which the balance point is found.
Electromotive Force (EMF) – The voltage generated by a cell or battery, which can be measured using a potentiometer.
