Blog Tag SCIENCE

Disadvantages of heating effects of current

When an electric current flow through a conductor, a part of the electrical energy is converted into heat energy. This is a waste of energy. The heat produced can damage the insulation on wire, damage electrical components or cause fires. Devices like TVs, music system and computers have vents to allow air to cool them. Computers even have fans f . . .

Overload

An electric overload occurs when too much current passes through electric wires. The wires heat and can melt, with the risk of starting a fire. For Example : In building the wires meant for light and fans can carry a certain amount of current safely. i.e. with overheating. If we connect a number of devices like lamps and heaters to the . . .

Risk of overload: things to avoid

Putting too much pressure on a water hose can make it burst. The principle is similar for electric wires: if too great a current flow is required by several items of equipment connected to the same line, this produces overload. Avoid therefore as far as possible: plugging several power-hungry items of equipment into the same socket using a m . . .

Relation of Short circuit with overload

A short circuit is a direct low resistance connection between two pointes across which there is a voltage. Due to overload (too much current flow) occurs short circuit. A short circuit is simply a low resistance connection between the two conductors supplying electrical power to any circuit. This results in excessive current flow in the power source . . .

Fuse

A fuse is an electrical safety device that operates to provide overcurrent protection of an electrical circuit including the source of power and the load. Its essential component is a metal wire or strip that melts when too much current flows through it Electric fuse is a protective device which protects electrical equipment in th . . .

Uses of the heating effect of current

Electric bulbs work because of the heating effect. A bulb has a long and thin tungsten filament (the curly wire inside). The filament has a higher resistance than ordinary wires. When a current passes through the filament it gets heated and starts to glow. But it does not melt because tungsten has a very high melting point. Electric heater, irons, to . . .

Construction of Fuse

The fuse wire is made of zinc, copper, silver, aluminum, or alloys to provide stable and predictable characteristics. Fuse should be of low resistance and low melting point as per the requirement current rating for overcurrent protection. . . .

Magnetic effect of electric current

The magnetic effect of electric current is known as electromagnetic effect. It is observed that when a compass is brought near a current carrying conductor the needle of compass gets deflected because of flow of electricity. This shows that electric current produces a magnetic effect. . . .

Electromagnet

An electromagnet is a magnet that runs on electricity. A magnet produced by passing an electric current through a coil (a length of wire wound closely together is called a coil) wound around a soft iron core is called an electromagnet. Unlike a permanent magnet, the strength of an electromagnet can easily be changed by changing the amount of electric cu . . .

Properties of electromagnet

An electromagnet’s strength depends on the number of turns of wire and the amount of current passing through it. An electromagnet is not a permanent magnet. Its magnetism lasts only while a current passes through its coil. Once the current stops, the iron core loses its magnetism. . . .

Uses of Electromagnet

Electromagnets have numerous uses some common ones are given below: Cranes with strong electromagnets are used to pick up iron objects. To put them down Electromagnets are also used for separating objects made of magnetic materials from others. A thin iron strip attracted by an electromagnet produces a sound as it strikes against the electroma . . .

Destructive Distillation

Destructive Distillation Destructive distillation is the process of heating complex substances such as coal in a limited supply of air so that it breaks down to form simpler substances. In this process coal is heated to 10000C in the absence of air to obtain different useful components, such as coke, coal tar and coal gas.   . . .

Electric bell

Electromagnets are used in electric bell Step 1: When we push the switch of the bell, electric current flows to the electromagnet. Step 2: The electromagnet attracts the soft iron strip. The hammer attached to the strip then hits gong, making it ring. Step 3: When the soft iron strip gets attracted to the electromagnet, it no longer touches the . . .

Number of division between Ice point and Steam point of Fahrenheit, Celsius and kelvin scale

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Vomiting- A reflex action

Vomiting is a reflex action which normally serves to protect the body against harmful substances. Vomiting is an antiperistaltic movement which begins as a contraction of muscles of the small intestine, pushing the intestinal content into the stomach via the opened pyloric sphincter. Contraction of stomach muscles force the contents into the oesop . . .

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