MCQ Chapter 9 General Science Class 7 Maharashtra Board MCQ For All Chapters – General Science Class 7Heat 1. What occurs when the water in the conical flask cools? It expands It contracts It remains unchanged It turns solidQuestion 1 of 202. Why is mercury used in a thermometer? It conducts heat poorly It expands and contracts with temperature It reflects heat It stays solidQuestion 2 of 203. What happens to a balloon fixed on a glass bottle when placed in hot water? It shrinks It expands It bursts immediately It stays the sameQuestion 3 of 204. What happens to the gas in the balloon when heat is removed? It expands It contracts It escapes It solidifiesQuestion 4 of 205. Who invented the thermos flask? Benjamin Franklin James Dewar Thomas Edison Albert EinsteinQuestion 5 of 206. What prevents heat conduction in a thermos flask? Silver coating Vacuum between tubes Metal jar Sponge piecesQuestion 6 of 207. Why does the silver coating in a thermos flask help retain heat? It conducts heat It reflects heat back It absorbs heat It creates a vacuumQuestion 7 of 208. What absorbs the most heat according to the document? White object Black object Blue object Silver objectQuestion 8 of 209. Which mode of heat transfer does not require a medium? Conduction Convection Radiation ReflectionQuestion 9 of 2010. What type of substance conducts heat well? Bad conductor Good conductor Insulator ReflectorQuestion 10 of 2011. Why are cooking utensils made of metals? They reflect heat They are bad conductors They are good conductors They contract easilyQuestion 11 of 2012. How does the earth receive heat from the sun? Conduction Convection Radiation ReflectionQuestion 12 of 2013. Which of these will absorb heat the most? Wooden board Glass vessel Iron griddle Plastic plateQuestion 13 of 2014. How does a cold compress lower a fever? By radiating heat By conducting heat from the forehead By reflecting heat By contracting the skinQuestion 14 of 2015. Why are houses in Rajasthan painted white? To absorb heat To reflect heat To conduct heat To contract lessQuestion 15 of 2016. Which mode of heat transfer causes sea breezes? Conduction Convection Radiation ReflectionQuestion 16 of 2017. Why is a glass bottle more likely to crack with boiling water than a borosil one? Glass conducts heat better Glass expands unevenly Borosil reflects heat Borosil contracts moreQuestion 17 of 2018. Why do telephone wires sag in summer? They contract They expand They reflect heat They lose weightQuestion 18 of 2019. Why does an iron pillar feel colder than a wooden pole in winter? Iron reflects heat Iron conducts heat away faster Wood expands more Wood radiates heatQuestion 19 of 2020. Why are heaters placed near the floor? To radiate heat upward To allow convection currents to rise To reflect heat downward To conduct heat to the ceilingQuestion 20 of 20 Loading...
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