Effects of Electric Current: Practice Questions Set 2

Title: Effects of Electric Current: Practice Questions Set 2

Question 1:
Discuss the different factors that affect the amount of heating produced by an electric current in a conductor.

Answer:
The amount of heating produced by an electric current in a conductor is influenced by several factors. These factors include:
1. Current: The greater the current flowing through a conductor, the more heat is produced.
2. Resistance: Higher resistance in a conductor leads to more heating. This is because resistance converts electrical energy into heat energy.
3. Time: The longer the current flows through a conductor, the more heat is generated.
4. Material of the Conductor: Different materials have different resistivities, which can affect the amount of heat produced. For example, materials with higher resistivities tend to produce more heat.

Question 2:
Explain why electric current causes a bulb to light up. Include the role of filaments in your explanation.

Answer:
When electric current passes through a bulb, it causes the filament inside the bulb to emit light. The filament is made of a material with high resistance, such as tungsten. Here's how it works:
1. The electric current flows through the filament, encountering resistance.
2. Due to the resistance, some of the electrical energy is converted into heat energy.
3. The heat energy causes the filament to become extremely hot.
4. When the filament reaches a high temperature, it starts glowing and emits light.

Question 3:
Describe the process of converting a conductor into a temporary magnet using the right-hand rule.

Answer:
The right-hand rule is a technique used to determine the direction of the magnetic field produced by a current-carrying conductor. Here's how you can use the right-hand rule to convert a conductor into a temporary magnet:
1. Hold the conductor in your right hand, with your thumb pointing in the direction of the current flow.
2. Wrap your fingers around the conductor. The curled fingers represent the direction of the magnetic field lines around the conductor.
3. As a result, the conductor becomes a temporary magnet with a magnetic field around it. The direction of the magnetic field follows the right-hand rule.

Question 4:
How do electric current-based heating devices regulate the amount of heat emitted? Provide an example.

Answer:
Electric current-based heating devices, such as heaters, regulate the amount of heat emitted using a thermostat. A thermostat is a device that senses the temperature and controls the flow of current accordingly. Here's how it works:
1. The thermostat measures the temperature in the vicinity of the heating element.
2. If the temperature is below the desired level, the thermostat allows more current to flow through the heating element, increasing the heat emitted.
3. If the temperature exceeds the set limit, the thermostat reduces the current flow, decreasing the heat output.
4. This process continues until the desired temperature is reached, maintaining a regulated amount of heat emission.
Example: An electric room heater with a built-in thermostat automatically switches on or off based on the room temperature, ensuring a comfortable level of warmth.

Question 5:
Conduct research on the hazards associated with electric current and discuss at least three safety measures that can be implemented to prevent accidents.

Answer:
Hazards associated with electric current include electric shock, electrical fires, and short circuits. To prevent accidents, the following safety measures can be implemented:
1. Insulation: Ensure that all electrical wires and cables are properly insulated to prevent accidental contact with live wires. Insulation acts as a barrier to protect against electric shock.
2. Grounding: Proper grounding of electrical appliances and equipment helps divert excess current to the ground, reducing the risk of electric shock.
3. Circuit Breakers: Install circuit breakers or fuses in electrical circuits. These devices automatically cut off the flow of current when there is an overload or short circuit, preventing electrical fires and damage to appliances.

Remember to always prioritize safety when dealing with electric current and consult a qualified electrician for any electrical work or repairs.

Keep up the great work, and if you have any more questions, feel free to ask!