Class 8 Science Chapter 12 MCQ

Here, all the statements are correct. Hence, your answer will be option [D].

An electroscope is a device, which is used to test whether an object is charged or not. It consists of closely place two metallic strips. When both the strips are charged with similar charges, they repel each other and become wide open.

Here, all the statements are correct. Hence, your answer will be option [D].

Here, all the statements are correct. Hence, your answer will be option [D].

When we rubbed a glass rod with silk cloth, the glass rod becomes positively charged. The silk cloth becomes negatively charged. The electric charges generated by rubbing are static electric charges. These electric charges remain bound on the surface of the charged object

The electric charges generated by rubbing are static electric charges. There are two types of charges; “Positive Charge and Negative Charge”. All the objects like glass rod, silk cloth, rubber balloon, ballpoint pen etc., are made up of tiny particles called atoms. We know that positive electric charges called protons and negative electric charge is called electrons. The object which loses negatively charged electrons during rubbing, acquires a positive electric charge. The object which gains negatively charged electrons during the rubbing, acquires a negative electric charge.

Benjamin Franklin is the scientist who showed that lightening is electric in nature. He discovered many things about lightening and was the first to show that a thunderstorm lets out electricity.

Here, all the statements are correct. Hence, your answer will be option [D].

After rubbing the glass rod with silk cloth, the glass rod becomes positively charged. The silk cloth becomes negatively charged. When a plastic comb is dry hair, it becomes negatively charged. The negatively charged comb induces a positive charge on the pieces of paper which are neutral in nature.

An earthquake is a sudden shaking or trembling of the earth which lasts for a very short time. It is caused by the disturbance deep down inside the uppermost layer of the earth called crust.

Here, all the statements are correct. Hence, your answer will be option [D].

The magnitude (or intensity) of an earthquake is expressed in terms of Richter scale.

Since earthquakes are caused by the movement of plates, the boundaries of the plates are weak zones where earthquake are more likely to occur. These weak zones are also known as seismic zones or fault zones.

The outermost layer of the earth is called “crust”. It is also known as earth’s crust.

The epicentre is the point on the “earth’s surface” vertically above the hypocentre (or focus), point in the crust where a seismic rupture begins.

Major earthquakes are less likely to occur in Odisha. The most threatened areas in India are Kashmir, Western and Central Himalayas, the whole of North-East, Rann of Kutch, Rajasthan and Indo-Gangetic Plane.

During a charging by rubbing (or by friction) process, the material that becomes negatively charged does so because it simply likes or gain electrons more than the material with which it is rubbed. The conductive abilities of the two materials has nothing to do with the subsequent result of the rubbing process.

Earthquake is a sudden shaking or trembling of the earth due to the collision between the earth’s plate or brushing past of one plate over the other. It can cause Tsunami, floods and landslides.

When we comb dry hair with plastic comb, friction takes place between two objects. Due to friction, hair losses some electrons to plastic comb. Due to loss of electron, the hair becomes positively charged and due to gain of electron, plastic comb becomes negatively charged.

Here, all the statements are correct. Hence, your answer will be option [D].

Here, all the statements are correct. Hence, your answer will be option [D].

Here, all the statements are correct. Hence, your answer will be option [D].

Here, all the statements are correct. Hence, your answer will be option [D].

Here, all the statements are correct. Hence, your answer will be option [D].

The whole crust of the earth is not in one piece. The crust of earth is made up of many huge pieces of flat rocks. Each pieces of the earth crust is called a plate. The crust of earth is divided into many plates. The plates of earth on which continents exist are called “continental plates” whereas those plates of earth on which oceans exist are called “oceanic plates”.