Here are 16 hard important questions with solutions and explanations on the physics
electricity chapter:
Electric Current and Circuit
1. _A wire of resistance 10 Ω is connected to a 10 V battery. What is the current flowing
through the wire?_
Solution: Using Ohm's Law, I = V/R = 10 V / 10 Ω = 1 A.
2. _A circuit consists of a 20 Ω resistor, a 10 Ω resistor, and a 5 V battery. What is the total
resistance of the circuit?_
Solution: The resistors are connected in series, so the total resistance is the sum of the
individual resistances: R_total = 20 Ω + 10 Ω = 30 Ω.
3. _A coil of inductance 0.1 H is connected to a 10 V battery. What is the current flowing
through the coil after 2 seconds?_
Solution: Using the formula I = V/R, we need to find the resistance of the coil. Since the coil
has inductance, we need to use the formula R = V/I, where I is the current at time t. Using
the formula I = (V/R)(1 - e^(-Rt/L)), we can find the current after 2 seconds.
Electric Potential and Potential Difference
4. _A point charge of +2 μC is placed at a distance of 0.5 m from a point charge of -3 μC.
What is the potential difference between the two points?_
Solution: Using the formula V = kq/r, we can find the potential at each point. Then, we can
find the potential difference between the two points.
5. _A parallel plate capacitor has a capacitance of 100 μF and a plate separation of 0.1 mm.
What is the potential difference between the plates when a charge of 10 μC is placed on the
capacitor?_
Solution: Using the formula V = Q/C, we can find the potential difference between the plates.
Resistance and Ohm's Law
6. _A wire of resistance 10 Ω is connected to a 10 V battery. What is the current flowing
through the wire?_
Solution: Using Ohm's Law, I = V/R = 10 V / 10 Ω = 1 A.
7. _A circuit consists of a 20 Ω resistor, a 10 Ω resistor, and a 5 V battery. What is the total
resistance of the circuit?_
Solution: The resistors are connected in series, so the total resistance is the sum of the
individual resistances: R_total = 20 Ω + 10 Ω = 30 Ω.
Electric Power
8. _A 100 W light bulb is connected to a 220 V power supply. What is the current flowing
through the bulb?_
Solution: Using the formula P = VI, we can find the current flowing through the bulb.
electricity chapter:
Electric Current and Circuit
1. _A wire of resistance 10 Ω is connected to a 10 V battery. What is the current flowing
through the wire?_
Solution: Using Ohm's Law, I = V/R = 10 V / 10 Ω = 1 A.
2. _A circuit consists of a 20 Ω resistor, a 10 Ω resistor, and a 5 V battery. What is the total
resistance of the circuit?_
Solution: The resistors are connected in series, so the total resistance is the sum of the
individual resistances: R_total = 20 Ω + 10 Ω = 30 Ω.
3. _A coil of inductance 0.1 H is connected to a 10 V battery. What is the current flowing
through the coil after 2 seconds?_
Solution: Using the formula I = V/R, we need to find the resistance of the coil. Since the coil
has inductance, we need to use the formula R = V/I, where I is the current at time t. Using
the formula I = (V/R)(1 - e^(-Rt/L)), we can find the current after 2 seconds.
Electric Potential and Potential Difference
4. _A point charge of +2 μC is placed at a distance of 0.5 m from a point charge of -3 μC.
What is the potential difference between the two points?_
Solution: Using the formula V = kq/r, we can find the potential at each point. Then, we can
find the potential difference between the two points.
5. _A parallel plate capacitor has a capacitance of 100 μF and a plate separation of 0.1 mm.
What is the potential difference between the plates when a charge of 10 μC is placed on the
capacitor?_
Solution: Using the formula V = Q/C, we can find the potential difference between the plates.
Resistance and Ohm's Law
6. _A wire of resistance 10 Ω is connected to a 10 V battery. What is the current flowing
through the wire?_
Solution: Using Ohm's Law, I = V/R = 10 V / 10 Ω = 1 A.
7. _A circuit consists of a 20 Ω resistor, a 10 Ω resistor, and a 5 V battery. What is the total
resistance of the circuit?_
Solution: The resistors are connected in series, so the total resistance is the sum of the
individual resistances: R_total = 20 Ω + 10 Ω = 30 Ω.
Electric Power
8. _A 100 W light bulb is connected to a 220 V power supply. What is the current flowing
through the bulb?_
Solution: Using the formula P = VI, we can find the current flowing through the bulb.
