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November 18, 2024Some Natural Phenomenon: Have you ever seen lightning in the sky? Have you noticed a sudden shaking or trembling of the Earth? Do you know how rains occur? These all are natural phenomena. A natural phenomenon is anything that occurs on its own without any human intervention. Some natural phenomena such as cyclones, thunderstorms, lightning, and earthquakes are destructive. However, we can protect and prepare ourselves from these natural disasters in various ways. In this article, we will discuss lightning, earthquakes, and rain. We will discuss how it occurs and how to get protected from these, and we will also learn to minimize its effects.
When the wires on an electric pole become loose, you might have seen sparks on it. It happens quite often when the wind is blowing and shaking the wires. So we can say that lightning is also an electric spark, but these sparks exist on a huge scale as we know that lightning is caused by the accumulation of charges in the cloud. We have to take precautions to protect ourselves from the deadly sparks of lightning and not be afraid of lightning. When lightning occurs, bright streaks of light are formed due to the transfer of a huge amount of charge, as shown in the below figure.
A small electric charge is acquired by rubbing a plastic refill with polythene. Similarly, when we rub a plastic comb with dry hair, it acquires a small charge. These objects are called charged objects.
Lightning safety:- When lightning and thunderstorm occurs, no open place is safe. But we can do certain precautions to protect, that is:
While creating a thunderstorm, the air currents travel upward, and the droplets of water move downward. Due to these movements, the burden in the clouds is separated, and it produces positive and negative charges. After this, near the upper edges of the clouds, the positive charges accumulated, and near the lower edges of the clouds, the negative charges accumulated. Positive charges are also accumulated near the bottom. Once charges accumulate, they become very high.
Under a normal environment, the air is a very poor conductor of electricity, but it can no longer resist its surge. As a result, the electrical charges transfer to the bottom and generate bright light and sound streaks throughout the sky. The process is understood as discharge.
Sudden shaking or trembling of the Earth, which last for a very short time, is called an earthquake. It is caused by a disturbance produced due to the movent of the Earth’s crust. Major earthquakes are much less frequent. They can cause immense damage to buildings, bridges, dams, and other people. The earthquake also causes floods, landslides, and tsunamis. The below image shows the destruction caused due to high-intensity earthquakes. There is often a tremendous loss to life and property.
The outermost layer of the Earth is fragmented, and each fragment is called a plate. These plates are in continual motion. When they brush past each other, or a plate goes under another because of collision, it causes disturbance in the Earth’s crust. It is this disturbance that shows up as an earthquake on the surface of the Earth. Although we all know it’s not yet possible to predict when and where a subsequent earthquake might occur. Due to the movement of the plates, earthquakes are caused.
Earthquakes are more likely to occur at the boundaries of the plates because they are weak zones. These weak zones are also known as seismic or fault zones. We can express the intensity of an earthquake in terms of magnitude on a scale that is known as the Richter scale. The point at which the intensity of an earthquake is felt most is called epicentre (shown in the below figure). It lies just above the focus of earthquake or hypocenter.
We know that earthquakes cannot be predicted, and we also know that earthquakes may be highly destructive. That’s why it is important to take the necessary precautions to protect ourselves all the time. People living in seismic zones have to be specially prepared, where earthquakes are more likely to occur. All the buildings should be so designed that they can withstand major tremors even in weak zones.
To make the structure ‘Quake Safe’ following steps should be taken.
If you are at home
If you are outdoors
When drops of the liquid fall from the clouds to the surface of the Earth is called rain. It is also called precipitation. When the water is absorbed from different water bodies, a large amount of it vaporizes and enters the atmospheric air. When the water evaporates, it rises above the ground level and cools after reaching a suitable height.
Condensation is the process in which water vapour turns into droplets of water on cooling. This droplet contains dust and other particles, which accelerates the process and forms the nucleus of these droplets and clamp together to form clouds. Then, they fall to the ground as rain once they grow big and heavy.
Hence, they are precipitations. If the temperature is low, these precipitations are sometimes in the form of snow, hail, or sleet. When rain occurs, it wets the roads and streets and can cause waterlogging (as shown in the below figure).
The regular circulation of water in different states of matter is called the water cycle or hydrological cycle. The following stages are followed by the water cycle that is:
Q.1. When is lightning seen?
Ans: When the negative charges from the clouds and the positive charges on the ground meet, a huge amount of energy is produced as bright light and sound. This is seen as lightning.
Q.2. Suggest three measures to protect ourselves from lightning.
Ans: We can protect ourselves from lightning by taking precautions such as switching off and disconnecting all heavy electrical appliances, not bathing under running tap water, not standing near metallic poles.
Q.3. What causes an earthquake?
Ans: Due to the movement of the plates deep down inside the uppermost layer of the Earth called the crust, sudden shaking of the Earth occurs; this is known as an earthquake. It is measured on Richter Scale.
Q.4. Explain the working of a seismograph.
Ans: The seismograph consists of a vibrating rod that starts vibrating when tremors occur. In the vibrating rod, a pen is attached to it that records the seismic waves on a paper which moves under it.
Q.5. What are the effects of rain?
Ans: The impact of rainwater striking the surface can cause soil erosion. Erosion is a concern for farmers as their valuable, nutrient-rich topsoil can be washed away from rainwater. Roads and bridges got damaged or weak due to heavy rain.
We hope this article on some natural phenomenon is helpful to you. If you have any questions related to this article or in general about natural phenomenons, drop your comments in the comment box below and we will get back to you as soon as possible.