How Well Do You Know About Kirchoff's Laws?

Kirchhoff's law can be used to analyze circuits. Kirchhoff's laws are fundamental principles in electrical circuit analysis. They are used to determine the voltages and currents in a circuit by considering the conservation of charge and energy. These laws provide a mathematical framework for analyzing complex circuits and are widely used in electrical engineering. Newton's law is related to the motion of objects, while Coulomb's law deals with the electrostatic force between charged particles. Therefore, neither of these laws is applicable for circuit analysis.

Kirchhoff's 1st law, also known as Kirchhoff's current law (KCL), deals with the conservation of electric charge in a circuit. It states that the total current entering a junction in a circuit is equal to the total current leaving that junction. This law is based on the principle of conservation of charge and is used to analyze and solve complex electrical circuits. Therefore, the correct answer is "Current in the circuit."

Kirchhoff's 2nd law, also known as Kirchhoff's voltage law (KVL), deals with the conservation of energy in an electrical circuit. It states that the sum of the voltages around any closed loop in a circuit is equal to zero. This law is used to analyze and solve complex circuits by considering the voltage drops and rises across different components in the circuit. Therefore, the correct answer is "Voltage and e.m.f in circuit."

Kirchhoff's First Law is also known as Kirchhoff's Current Law. This law states that the algebraic sum of currents meeting at any node (junction) in an electrical circuit is zero. In other words, the total current flowing into a node is equal to the total current flowing out of that node. This law is based on the principle of conservation of charge in a circuit.

When resistances are connected in parallel, the combined resistance is given by the formula: 1/R = 1/R1 + 1/R2 + 1/R3 + ... In this case, the combined resistance is 1/R = 1/20 + 1/30 + 1/60. Simplifying this equation gives 1/R = 3/60 + 2/60 + 1/60 = 6/60 = 1/10. Taking the reciprocal of both sides gives R = 10 Ω, so the combined resistance is 10 Ω.

Kirchhoff's 1st law is the consequence of the law of conservation of charge. This law states that the total amount of electric charge in a closed system remains constant over time. According to Kirchhoff's 1st law, the sum of currents entering a junction in an electrical circuit is equal to the sum of currents leaving the junction. This is based on the principle that charge cannot be created or destroyed, only transferred or redistributed within a system.

Voltage is the correct answer because it represents the difference in electrical potential energy between two places. It is a measure of the electric potential difference or the force that pushes electric charges through a circuit. Voltage is measured in volts and determines the flow of current in a circuit.

When two resistors are connected in parallel, the equivalent resistance is calculated using the formula 1/Req = 1/R1 + 1/R2. In this case, the two resistors have the same value of 10 Ω. Plugging in the values, we get 1/Req = 1/10 + 1/10 = 2/10. Simplifying, we find that 1/Req = 1/5. Taking the reciprocal of both sides, we get Req = 5 Ω. Therefore, the equivalent resistance of the two 10 Ω resistors connected in parallel is 5 Ω.

Kirchhoff's second law, also known as Kirchhoff's loop rule, states that the sum of the electromotive forces (e) in any closed loop of a circuit is equal to the sum of the products of the current (I) and resistance (R) in that loop. This equation, ∑e = ∑IR, accurately represents Kirchhoff's second law. Kirchhoff's third law and junction rule are not applicable in this context.

When resistors are connected in series, the current flowing through each resistor remains the same. This is because the current in a series circuit has only one path to flow through, and it encounters the same resistance in each resistor. Therefore, the current does not increase or decrease, but stays constant throughout the circuit.