Practice Questions

<p>A household circuit is protected by a fuse rated at 10 A. If several appliances are connected to the circuit, and the total current exceeds 10 A, what will happen and why is this a safety feature?</p>

<p>State one safety measure to prevent unnecessary heating in household switchboards.</p>

<p>Define the term &#39;magnetic effect of electric current&#39;.</p>

<p>List two applications of the magnetic effect of electric current.</p>

<p>Identify the material commonly used as the core of an electromagnet to make it stronger.</p>

<p>Name the two terminals of a Voltaic cell.</p>

<p>Describe what an electromagnet is.</p>

<p>Define the term &#39;heating effect of electric current&#39;.</p>

<p>Describe the energy transformations that occur in an electric heater. Start from the electrical energy supplied and end with the heat released.</p>

<p>Name the two poles of an electromagnet.</p>

<p>Identify two metals that can be used as electrodes in a Voltaic cell.</p>

<p>A simple electromagnet is made by wrapping a wire around an iron nail and connecting it to a battery. If you want to increase the strength of this electromagnet, what two changes could you make?</p>

<p>Explain why a compass needle deflects when brought near a current-carrying wire.</p>

<p>An electromagnet is used in a scrapyard to lift heavy iron beams. If the electromagnet suddenly stops working, what could be two possible reasons for this failure?</p>

<p>What is the primary difference between a dry cell and a voltaic cell in terms of their electrolyte?</p>

<p>A student constructs an electromagnet and finds it can lift 10 paperclips. If the student doubles the current flowing through the coil, predict how many paperclips the electromagnet can now lift, assuming a direct relationship.</p>

<p>A coil of wire is wrapped around an iron nail. When connected to a battery, the nail attracts iron filings. If the battery is replaced with one that provides a higher voltage, what will happen to the number of iron filings attracted?</p>

<p>List three factors that the heat generated in a wire depends on.</p>

<p>Explain how the strength of an electromagnet can be increased.</p>

<p>Describe how a battery generates electricity.</p>

<p>Explain how increasing the number of turns in a coil affects the strength of an electromagnet. Provide a practical example.</p>

<p>Why are rechargeable batteries considered more environmentally friendly than non-rechargeable batteries? Explain your reasoning.</p>

<p>Describe the main difference between a dry cell and a Voltaic cell.</p>

<p>A copper wire and a nichrome wire of the same length and thickness are connected to the same battery. Analyze which wire will get hotter and explain why.</p>

<p>A heating element in an electric kettle has a resistance of $44 \Omega$ and is connected to a $220$ V power supply. Calculate the power dissipated by the heating element.</p>

<p>Explain why rechargeable batteries are considered advantageous compared to single-use cells.</p>

<p>A student observes that a compass needle deflects when placed near a wire connected to a battery. Analyze what happens to the compass needle if the battery&#39;s polarity is reversed.</p>

<p>An electric iron is rated at 750 W and operates on a 220 V supply. Calculate the current drawn by the electric iron.</p>

<p>A student uses a lemon cell to light an LED. If the LED does not light up initially, explain two possible reasons why and how the student can troubleshoot the problem.</p>

<p>Explain what an electrolyte is in the context of a Voltaic cell.</p>