Author Archives: Abdul Wahab

Ohm’s Law

Ohm’s law is the fundamental law in the field of electricity. It was discovered by George Ohm, and named after him. Ohm’s law provides the relationship between current, voltage, and resistance. It states that, the voltage across any resistance is equal to current times the resistance.

V = I*R

You can also find the current and resistance from the ohm’s law.

I = V/R   and   R = V/I

Ohm’s Law Triangle

If you want to easily remember the ohm’s law without confusing between the formulas. Try the triangle given below.


Ohm’s law triangle

In this triangle, all the three quantities are given. Follow the steps below to find the voltage, current, and resistance.

  • To find the voltage, just place the hand on V. You will see that, ‘I’ and ‘R’ are in multiplication form, just multiply them and get the voltage.
  • To find the current, place the hand on ‘I’ and you will see that, ‘V’ and ‘R’ are in division form. Just divide the V by R to get the current.
  • To find the resistance, place you hand on ‘R’, and you will see that, ‘V’ and ‘I’ are in division form. Divide the V by I to get the resistance.


Solve the following problems to get a grip on the ohm’s law.

Problem 1: The current through a resistor is measured to be 5 amperes. The resistance of the resistor is 10 ohms. What is the voltage across the resistor?


Use the ohm’s law relation:

V = I*R

V = 5 * 10 = 50 volts

Problem 2: Voltage across a resistor was found to be 12 volts, and the current through it was 0.5 amperes. What is the resistance of the resistor?


Use the ohm’s law relation:

R = V/I

R = 12/0.5 = 24 ohms

Problem 3: Voltage across a resistor was measured to be 50 volts. The value of the resistor is 100 ohms. What is the current through it?


Use the ohm’s law relation:

I = V/R

I = 50/100 = 0.5 amperes

Fun Facts

  • Voltmeter is used to measure the voltage across any component in a circuit.
  • Ammeter is used to measure the current in a circuit.
  • Multimeter is device used to measure voltage, current, and resistance. Some multimeters can also measure temperature.

Electronic Circuit

What is Electronic Circuit?

An electronic circuit is a path, in which electric current can flow. A basic circuit is the combination of electrical components, which are wired together. The electronic circuit is made to do a certain job out of electricity.


The drawing of an electric circuit is called schematic. It is used to simplify the electronic circuit so that we can understand how the components are connected together. All the electrical components are represented by their symbols, called schematic symbol.


Some schematic symbols used in circuits

Series Circuit

When the electronic components are connected in series with each other and power source, they are called to be connected in series. In a series connection, the components are connected in head-to-tail fashion. Consider the following example of a series circuit, in which resistors are connected in series.


Series resistors circuit

In a series circuit the current in the all components is same, but the voltage is divided among them.

Parallel Circuit

A parallel circuit is the combination of electrical components in parallel with each other and the power source. In parallel circuits, components are connected in head-with-head and tail-with-tail fashion. Consider the following schematic of the parallel circuit, in which resistors are connected in parallel.


Parallel resistors circuit

In a parallel circuit, the current is divided into each branch. But, the voltage of each branch is same.

Series-Parallel circuit

This circuit has both kinds of connections. Some components are connected in series and some components are connected in parallel. To deal with the series-parallel circuit, each branch of the circuit is considered separately for understanding the behavior of the circuit.


Series-parallel resistors circuit

Consider the following circuit, in which the resistors are connected in series and parallel combination.

Ground of the Circuit

A ground is the reference point in a circuit. This point works as a return path for the electrical current back to the source. Every circuit has at least one ground. However, a circuit can have more than one ground. The voltage across each electronic component is measured with respect to ground.

The schematic symbol of the ground is:


circuit ground symbol

Interesting Facts

  • The processor of a computer is a very complex circuit, which contains billions of transistors.
  • Digital circuit carries the signal, that represents only zeros or ones.
  • Analog circuits have a signal which varies in a continuous manner.

Conductors and Insulators

Electricity is the flow of electrons, called electric current in a circuit (path for electrons). Electric current tends to follow the easiest path in a circuit. Some materials are good at passing an electric current through them, while others completely block the current. These materials are called conductors and insulators.


Conductors are the materials which provide the easiest path to the electric current. Current easily travel through the conductors without any difficulty. Conductors provide a good path to the electric current because they contain loosely bound (free to move) electrons in their atoms. Conductors are used to carry electric current in a circuit. You probably have seen the electric wires connected to the electric appliance; these are made of conductors.

Copper wire

Good conductors of the electric current are the metals because they contain loose electron. But, the most conductive metal is silver. Silver is a precious and costly metal, so it is not commonly used in the electric circuits. Instead, copper is used which is cheaper than the silver and also a good conductor.

Some good conductors are:

  • Silver
  • Copper
  • Gold
  • Aluminum
  • Iron


Insulators are the materials which resist or block the electric current from passing through them. You may also call them bad conductors. They don’t provide a good path to electric current because they don’t contain loosely bound electron in their atoms. Instead, their electrons are tightly packed with atoms. Insulators are mostly used to insulate the conductors. So, if anybody accidently touches them, he won’t get electrocuted.

Some materials have very good insulations property, like rubber and glass. While other have poor insulation property, like water, wet wood etc. Humans are also the bad conductors and bad insulators. Means if the voltage is high, we can easily be electrocuted (don’t ever touch the 110V or 220V lines).

Some good Insulators are:

  • Porcelain
  • Rubber
  • Plastic
  • Paper
  • Glass

Interesting Facts

  • The material that is a good conductor of electric current also conducts heat easily.
  • Aluminum is not good conductor as copper. But, it is so cheap that it used in the transmission lines used to supply electricity to houses, building, and factories.
  • Increasing temperature decreases the conductivity of a conductor.


What are Clouds?

We often talk about the weather in terms sunny day or cloudy one. Clouds cover the sky and block the sunlight from passing through them. These clouds are made of tiny droplets of water and ice crystals. They float above in the atmosphere. Sometimes their color is white and sometimes dark. The Study of the clouds and their formation helps in predicting the weather accurately.

How Clouds form?

Hot air has the capability of holding more water than the cold air. When the hot air rises above in the atmosphere and cools again, the water that it carries condenses into the small droplets. As a result, the clouds is formed.

How do clouds float?

Clouds are made of very small droplets. These droplets fall very slowly, much like dust specs. But, the hot constantly rise above, which also rise the droplets again. This results into the floating droplets that don’t fall and continue to remain above in the atmosphere.

Types of Clouds

There are the 10 types of clouds according to their level in the atmosphere. These types are:
cloud types

  1. High Clouds: These clouds are mostly in frozen form. They are formed 20,000 feet above the ground. The types of high clouds are Cirrus, Cirrocumulus, and Cirrostratus.
  2. Middle Clouds: This cloud is made of both water droplets and ice crystals. They form between 6,500 and 20,000 feet above the ground. Middle clouds include altostratus, altocumulus, and nimbostratus.
  3. Low Clouds: These are low lying clouds which form below the 6,500 feet altitude. They are mostly made of droplets. These clouds include stratus and stratocumulus.
  4. Vertical Clouds: These are the longest clouds which are formed 1,000 feet above the ground. But, their size increases up to 60,000 feet high. This type of clouds includes cumulus and cumulonimbus.

Fun Facts

  • When the clouds are formed on the ground, they are called fog.
  • When rain and snow fall the clouds, it is called precipitation.
  • Clouds can have millions of tons of water stored in them.
  • Other chemicals can also make clouds. Jupiter’s and Saturn’s clouds are mostly made of ammonia.


Butterflies are one of the beautiful insects found across the world. They are known mostly for their large beautiful colored wings. their wings have a lot of colors in many different patterns. The bright colors also provide a good camouflage to them for avoiding predators. Butterflies also play an important role in ecosystems. They help the plant in pollination.
greenish Butterfly

How do butterflies look like?

Butterflies are the insects with wings. Their body is divided into 3 segments, which are head, thorax, and abdomen. They have six legs which are connected to their thorax. Moreover, they have a pair of antenna, large and wide wings, and a pair of compound eyes.

Butterflies can fly with wings, only when they are warm. They usually sit in the sunlight to warm-up their bodies and wings. Butterflies have compound eyes, which gives them a benefit of detecting fast motion of the objects. Also, they can see the ultraviolet region of the light which humans can’t see.

Diet of Butterflies

Adult butterflies love to eat the pollen of the flowers. In turn, they help in the pollination process of plants to help them fertilize. Mostly, they like to eat liquid pollen, like the juice of the fruits and sap of some plants. Butterflies sip the food with their long and flexible tongue called proboscis.


Butterfly is eating nectar

Habitat of Butterflies

Butterflies are found in almost every part of the world, including hot, cold, dry, and moist areas. They are also found high in the mountains and at the sea levels. Butterflies also migrate from one region to other to find a more habitable place for them. Some species of butterflies are able to migrate a distance of 2,500 miles.

Interesting Facts

  • Some species of the butterflies can reach a speed of 40 mph.
  • The largest butterfly found on the Earth is Queen Alexandria’s birdwing butterfly. It can grow 11 inches long.
  • Butterflies have very delicate wings, they can be damaged by just holding them.
  • 18,500 species of the butterflies have been found across the world.