Grade 8 Science: Electricity - Magnetic and Heating Effects

Vocabulary flashcards focusing on definitions, key scientists, and essential concepts related to the magnetic and heating effects of electric current and cell technologies.

Magnetic Effect of Electric Current

The phenomenon in which an electric current flowing through a conductor (such as a wire) produces a magnetic field around it.

Magnetic Field

The region around a magnet or a current-carrying wire where its magnetic effect can be felt, such as by the deflection of a compass needle.

Hans Christian Oersted

A professor at a university in Denmark who discovered in 1820 that electricity and magnetism are linked after noticing that a compass needle deflected whenever an electrical circuit was closed or opened.

Electromagnet

A current-carrying coil that behaves as a magnet, typically featuring an iron core to increase its magnetic strength.

Lifting Electromagnets

Strong electromagnets hung on cranes, controlled by switching the electric current ON and OFF, used in factories and scrap yards to move, lift, and sort heavy metal items.

Heating Effect of Electric Current

The process where a conductor gets heated when electric current passes through it, caused by the conductor's opposition or resistance to the flow of current converting electrical energy into heat energy.

Heating Element

A rod or coil of wire in household electric heating appliances (such as room heaters, stoves, kettles, irons, and hair dryers) that converts electric current into heat.

Furnace

An enclosed space built to generate high heat; in steel manufacturing industries, specially designed high-temperature furnaces use electric current to melt and recycle scrap steel.

Voltaic Cell

Also known as a Galvanic cell, an early electric cell consisting of two metal rods (electrodes) made of different materials partly dipped in a liquid electrolyte.

Electrolyte

A liquid (such as a weak acid or salt solution) or a thick moist paste inside a cell that reacts chemically with electrodes to produce or conduct electricity.

Electrodes

Metal rods or strips made of different materials partly dipped in an electrolyte inside a cell, acting as positive and negative terminals.

Alessandro Volta and Luigi Galvani

Italian scientists from the late 1700s after whom Voltaic and Galvanic cells are named; Volta showed that combining different metals with a liquid electrolyte generates an electric current.

Dry Cell

A single-use electric cell consisting of a zinc container acting as the negative terminal, a central carbon rod with a metal cap acting as the positive terminal, and a thick moist paste electrolyte.

Rechargeable Batteries

Batteries that can be recharged and reused multiple times, commonly used in laptops, mobile phones, cameras, inverters, and electric vehicles.

Lithium-ion (Li-ion) Battery

The most common type of rechargeable battery in modern electronics, relying on special metals like lithium and cobalt.

Solid-state Batteries

An advanced battery technology being developed that replaces liquid or paste-like electrolytes with solid materials to increase safety, charging speed, and lifespan.