CBSE Class 10 Science Notes Chapter 12 Electricity

CBSE Class 10 Science Notes - Chapter 12: Electricity

Electric Current: The flow of electric charge through a conductor, measured in amperes (A). It’s caused by the movement of electrons.
Potential Difference: The difference in electric potential energy between two points, measured in volts (V). It drives the flow of current.
Ohm’s Law: V = IR, where V is the voltage, I is the current, and R is the resistance. It states that current is directly proportional to the voltage and inversely proportional to the resistance.
Resistance: The opposition to the flow of current, depends on material, length, cross-sectional area, and temperature.
Power: The rate at which electrical energy is used, calculated as P = VI (Power = Voltage × Current).
Heating Effect of Current: When current flows through a conductor, it produces heat. This is used in appliances like electric heaters.

Most Important Science Class 10 Questions Answers For Board Examination

Here are some of the most asked questions from Chapter 12 (Electricity) of CBSE Class 10 Science in the last 5 years:

State Ohm’s Law. Explain how it is used to determine the resistance of a conductor.
- Answer: Ohm’s Law states that the current through a conductor is directly proportional to the potential difference across its ends, provided the temperature remains constant. The formula is V = IR, where V is voltage, I is current, and R is resistance.
What is the relationship between electric power and energy?
- Answer: Power is the rate at which electrical energy is consumed or converted. It is calculated as P = VI, where P is power, V is voltage, and I is current. Electrical energy is given by the formula E = P × t, where t is time.
Define resistance. What factors affect it?
- Answer: Resistance is the opposition to the flow of electric current, measured in ohms. Factors affecting resistance include the material of the conductor, length, cross-sectional area, and temperature.
Explain the heating effect of electric current with an example.
- Answer: When current flows through a conductor, it produces heat due to collisions between electrons and atoms. This effect is used in devices like electric heaters, where the current passing through the filament produces heat.

Here are some multiple-choice questions (MCQs) related to Chapter 12 (Electricity) of CBSE Class 10 Science:

What is the SI unit of electric current?
- a) Volt
- b) Ampere
- c) Ohm
- d) Coulomb
- Answer: b) Ampere
Which of the following is the correct formula for electric power?
- a) P = I²R
- b) P = V²R
- c) P = IV
- d) All of the above
- Answer: d) All of the above
What does Ohm’s law state?
- a) V = IR
- b) V = I/R
- c) V = I + R
- d) V = I²R
- Answer: a) V = IR
The resistance of a conductor depends on which of the following factors?
- a) Length of the conductor
- b) Area of cross-section
- c) Material of the conductor
- d) All of the above
- Answer: d) All of the above
Which of the following is a good conductor of electricity?
- a) Plastic
- b) Rubber
- c) Copper
- d) Wood
- Answer: c) Copper