Mnemonics: Magnetic and Heating Effects | Science Curiosity Class 8 - New NCERT PDF Download

 1. Factors Affecting Strength of an Electromagnet 

Mnemonic: "More Current Turns Strong Magnet"

• More: Greater electric current → stronger magnetic field.
• Current: Flow of electricity in the coil → generates magnetism.
• Turns: More turns of wire in the coil → increases strength.
• Strong: These factors together strengthen the field.
• Magnet: Electromagnet — a temporary magnet formed by current.

Electromagnet

 2. Factors Affecting Heat Produced in a Conductor 

Mnemonic: "Smart Wires Last Longer Time"

• Smart (Material): The type of material decides resistance and heat.
• Wires (Thickness): Thin wires resist more and heat more.
• Last (Length): Longer wires → higher resistance → more heat.
• Time (Time): More time → more heat generated.

 3. Parts of a Voltaic Cell 

Mnemonic: "Every Plate Loves Energy"

• Every: Electrodes (two metal plates) — conduct electricity.
• Plate: Plates partly dipped in electrolyte — facilitate chemical reaction.
• Loves: Liquid electrolyte (acid or salt solution) — enables ion flow.
• Energy: Produces electric current — generates electricity.

 4. Parts of a Dry Cell 

Mnemonic: "Zebra Can Eat"

• Zebra: Zinc container (negative terminal) — acts as anode.
• Can: Carbon/ Graphite rod (positive terminal) — acts as cathode.
• Eat: Electrolyte paste — facilitates ion movement.

 5. Uses of Electromagnets 

Mnemonic: "Lovely Motors Bring Loud Fun"

• Lovely: Lifting electromagnets (cranes, scrap yards) — lift heavy metal objects.
• Motors: Electric motors — convert electrical energy to mechanical motion.
• Bring: Electric bells — use electromagnets for ringing mechanism.
• Loud: Loudspeakers — convert electrical signals to sound.
• Fun: Fans — use electromagnets for rotation.

 6. Common Household Appliances Using Heating Effect 

Mnemonic: "Hot Room Stays Warm Inside Kettle Hairdryer"

• Hot: Room heater — warms rooms using heating element.
• Room: Electric stove — cooks food with heat from current.
• Stays: Electric kettle — heats water for boiling.
• Warm: Water heater / immersion rod — heats water for bathing or use.
• Inside: Electric iron — smooths clothes with heat.
• Kettle: Kettle (repeated for emphasis in cue) — boils water.
• Hairdryer: Hair dryer — dries hair using heated air.

 7. Common Electrodes in Voltaic Cells 

Mnemonic: "Zebra Catches Silver Apples In Market Lane"

• Zebra: Zinc — commonly used as an electrode.
• Catches: Copper — frequently used in voltaic cells.
• Silver: Silver — used in specific cell types.
• Apples: Aluminium — lightweight electrode material.
• In: Iron — used in certain voltaic cells.
• Market: Magnesium — reactive electrode material.
• Lane: Lead — used in lead-acid batteries.

 8. Advantages of Rechargeable Batteries 

Mnemonic: "Reuse Saves Money Often"

• Reuse: Reusable many times — can be recharged and used repeatedly.
• Saves: Reduces wastage — less need for disposable batteries.
• Money: Cost-effective over time — saves money in the long run.
• Often: Common in many devices — widely used in electronics.