alleryHow does the resistance of a metallic wire change when it is made thicker, keeping its length and material the same?
AResistance increases
BResistance decreases
CResistance stays equal
DResistance becomes zero
Answer & Solution
Correct answer: B. Resistance decreases
1. Resistance is inversely proportional to cross-sectional area: $R \propto \dfrac{1}{A}$.
2. Making the wire thicker increases its area $A$.
3. A larger area means a smaller resistance, so resistance decreases.
4. It does not stay constant because area is changing.
_Source: Samacheer Kalvi (TN SCERT) Class 10 Science, Unit 4 Electricity "Electricity", p.63_
Keep practising Effects of Electric Current
Browse all Effects of Electric Current questions for Tamil Nadu SSLC (Class 10), or explore more Science topics.
Related questions
Fill the Ohm's-law blanksWhat is the role of the earth (ground) wire in a domestic electric circuit?A wire of resistance R is cut into five equal parts. What is the resistance of each part?Two resistors give 2 ohm when joined in parallel and 9 ohm when joined in series. What areA wire of resistance 10 ohm is stretched uniformly until its length becomes three times thWhy does a bulb glow when the switch in a simple circuit is closed?A torch bulb is rated 3 V and draws a current of 600 mA. What electric power does it consuAn electric heater of power 1000 W is used for 3 hours every day. How much electrical ener