🔍 Key Concepts

• DC (Direct Current) vs AC (Alternating Current) and how current direction is defined • Use of a magnetic field around a conductor to infer current direction • Purpose of an ammeter and what its polarity markings indicate

💭 Think About

• Which hand rule (left or right) is associated with conventional current direction for a straight conductor and its magnetic field? • If you place a magnetic compass near a straight DC conductor, what does the needle actually tell you about the magnetic field and hence current direction? • What does connecting an ammeter with marked + and – terminals in series tell you about which way the current is flowing?

✅ Before You Answer

• Recall which hand rule is used for conventional current in a straight wire creating a magnetic field (thumb = current, fingers = magnetic field). • Verify whether a magnetic compass alone can distinguish current direction without using a hand rule. • Confirm that when an ammeter is connected with known polarity, the deflection or indication shows the direction of current relative to its + and – terminals.