MCQ Science and Technology Class 9 Chapter 2 Maharashtra Board Work and Energy 1. What is the work done when catching a ball thrown by a friend?PositiveNegativeZeroInfiniteQuestion 1 of 202. What is the work done when swinging a stone tied to a string in a circular path?PositiveNegativeZeroInfiniteQuestion 2 of 203. What is the work done when stopping a moving car by applying brakes?PositiveNegativeZeroInfiniteQuestion 3 of 204. What is the kinetic energy gained by an object when a force displaces it?K.E.= mghK.E.= F sK.E.= ½ mv²K.E.= mvQuestion 4 of 205. What energy transformation occurs when a compressed spring is released?Kinetic to potentialPotential to kineticKinetic to thermalPotential to soundQuestion 5 of 206. What is the total energy of an object at a height x below its initial height h in free fall?T.E.= mghT.E.= mgxT.E.= mg(h - x)T.E.= ½ mv²Question 6 of 207. What is the relationship between joule and kilowatt-hour?1 kWh = 3.6 × 10^6 J1 kWh = 3.6 × 10^3 J1 kWh = 3.6 × 10^9 J1 kWh = 3.6 × 10^12 JQuestion 7 of 208. Who is the unit of power named after?Isaac NewtonJames WattAlbert EinsteinNikola TeslaQuestion 8 of 209. What is the kinetic energy of a freely falling object just before it reaches the ground?K.E.= 0K.E.= mghK.E.= ½ mghK.E.= 2mghQuestion 9 of 2010. How much electricity is consumed by a 1200 W iron used for 30 minutes daily in April (30 days)?18 units36 units9 units72 unitsQuestion 10 of 2011. If a ball’s energy is reduced by 40% after falling from 10 m, how high will it rebound?4 m6 m8 m10 mQuestion 11 of 2012. How much work is done when a car’s velocity increases from 54 km/h to 72 km/h (mass = 1500 kg)?131250 J262500 J65625 J525000 JQuestion 12 of 2013. How much work is done by applying a 10 N force over 30 cm in the same direction?3 J30 J0.3 J300 JQuestion 13 of 2014. Why is the work done on an object moving with uniform circular motion zero?Because force is zeroBecause displacement is zeroBecause force and displacement are perpendicularBecause velocity is constantQuestion 14 of 2015. If an object has zero momentum, does it have kinetic energy?YesNoSometimesDepends on massQuestion 15 of 2016. When is the potential energy of a body least?Sitting on a chairStanding on the groundSleeping on the groundSitting on the groundQuestion 16 of 2017. If a car’s velocity increases four times, how does its potential energy change?DoublesQuadruplesRemains unchangedBecomes 16 timesQuestion 17 of 2018. What is the total energy of a freely falling object at any point during its fall?T.E.= ½ mv²T.E.= mghT.E.= mgxT.E.= 0Question 18 of 2019. What type of energy does an electric fan running on electricity primarily produce?Potential energyKinetic energySound energyThermal energyQuestion 19 of 2020. What is the role of the National Physical Laboratory mentioned in the document?To develop new energy sourcesTo establish national standards of physical quantitiesTo manufacture scientific instrumentsTo teach physics principlesQuestion 20 of 20 Loading...
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