Ncert – class 8- science – Chapter 12: Some Natural Phenomena 2 Welcome to your Ncert - class 8- science - Chapter 12: Some Natural Phenomena 2 1. __________ is engineered to protect an elevated structure in the event of lightning strike. A lightening shield Copper wire All of the above A lightning conductor None 2. Why are lightning conductors pointed in shape? It allows more current. It attracts more electric charge due to very small radius and hence small surface area. To reduce mass. It repels the incident lightning discharge. None 3. Which of the following one must do when caught in a Thunderstorm? Take shelter under an umbrella with a metallic end Take shelter inside an isolated tree Sit near a window Take shelter in a safe place like car or bus None 4. Clouds get electrically charged when : Air molecules rub against water molecules The UV rays of sun falls on them 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 None 5. Why shouldn't one stand under a tree or a tall building during a thunderstorm? Lightning can strike trees and buildings, None of the above, Trees and buildings do not offer enough escape ground, Trees and buildings may fall causing damage, None 6. What kind of material should be used in an earthquake prone area? light weight heavy weight conducting material any of the above None 7. A lightning conductor consists of a conductor fixed on top of the building. several sharp metal spiked connected to a thick copper strip. all of the above a metal plate buried deep inside the ground connected to the ground end of copper strip. None 8. Lightning is a more common phenomenon during rainy season because of: high humidity solar electrostatic disturbances moderate temperature high atmospheric density None 9. What happens when you touch the water pipeline in the building during a thunderstorm? Your body provides earthing Your body will conduct electricity All of the above Charges will pass through your body None 10. The sparks caused due to friction between two machine parts are: lightning on a very small scale none of the above similar to lighting not similar to lightning None 11. 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. All of the above. Metal column used during construction. None 12. 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. Run to their houses Stand under a tree Squat down Just stand at their places None 13. 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 and stand under an electric pole Get out of the car and take cover under the car Remain in the car Run to a nearby tree 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. no reaction will be observed. both balloon and tumbler attract each other. the balloon will burst. None 15. The lightning conductor used in building, protects the building by: Conducting the lightning safely to the ground Dissipating the electric charge away from the building None of these Absorbing the electric charge 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.
