Ncert – class 8- science – Chapter 12: Some Natural Phenomena 2 Welcome to your Ncert - class 8- science - Chapter 12: Some Natural Phenomena 2 1. Explore and answer :Some children are playing in the playground. Suddenly clouds gather in the sky and there is thunder and lightning. What should they do now?The children should_______.Choose the correct answer. Squat down Run to their houses Just stand at their places Stand under a tree None 2. __________ is engineered to protect an elevated structure in the event of lightning strike. All of the above Copper wire A lightening shield A lightning conductor None 3. Lightning is a more common phenomenon during rainy season because of: solar electrostatic disturbances moderate temperature high humidity high atmospheric density None 4. Why shouldn't one stand under a tree or a tall building during a thunderstorm? Trees and buildings may fall causing damage, None of the above, Lightning can strike trees and buildings, Trees and buildings do not offer enough escape ground, None 5. What kind of material should be used in an earthquake prone area? light weight any of the above conducting material heavy weight None 6. Clouds get electrically charged when : Cold currents of air rub against hot currents of air Both Air molecules rub against water molecules and Cold currents of air rub against hot currents of air The UV rays of sun falls on them Air molecules rub against water molecules None 7. Other than lightning conductor, what are the objects which indirectly protect building from lightning / thunderstorm? Water pipe in the building. Electrical wires in the building. Metal column used during construction. All of the above. None 8. What happens when you touch the water pipeline in the building during a thunderstorm? Your body will conduct electricity Charges will pass through your body Your body provides earthing All of the above None 9. Suppose you are in a car and it is raining heavily with thunderstorms. Then what is the best way to protect yourself from a possible lightning strike? Get out of the car and take cover under the car Get out and stand under an electric pole Remain in the car Run to a nearby tree None 10. The sparks caused due to friction between two machine parts are: none of the above similar to lighting not similar to lightning lightning on a very small scale None 11. The lightning conductor used in building, protects the building by: Dissipating the electric charge away from the building Absorbing the electric charge None of these Conducting the lightning safely to the ground None 12. Which of the following one must do when caught in a Thunderstorm? Take shelter inside an isolated tree Sit near a window Take shelter under an umbrella with a metallic end Take shelter in a safe place like car or bus None 13. Why are lightning conductors pointed in shape? To reduce mass. It allows more current. It attracts more electric charge due to very small radius and hence small surface area. It repels the incident lightning discharge. None 14. Rub a glass tumbler with wool. Bring an inflated charged balloon, rubbed with wool, near refill. Then both balloon and tumbler will repel each other. both balloon and tumbler attract each other. no reaction will be observed. the balloon will burst. None 15. A lightning conductor consists of a conductor fixed on top of the building. all of the above several sharp metal spiked connected to a thick copper strip. a metal plate buried deep inside the ground connected to the ground end of copper strip. None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
