Question

1. Pd between terminals when k is open is called

• emf
• lost voltage
• terminal voltage
• induced voltage

2. Give an equation connecting R, r, I and E What is the value of E for open circuit and ideal cell.

3. What happens to terminal voltage if current increases

• for an ideal cell
• for an ordinary cell.

Answer 1

1. e.m.f

2. E = I(r+R).

3. For ideal cell, internal resistance is zero. Hence E = v. ie. terminal voltage does not change with current.

For ordinary cell, when current increases, V decreases.