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$An adiabatic change is the one in which.(a) No heat is added to or taken out of system.(b) No change of temperature takes place.(c) Boyles law is applicable.(d) Pressure and volume remains constant.$  $A thermos flask containing milk as a system is shaken rapidly. Does the temperature of milk rise?$  $Show that ratio of the root mean square speeds of molecules of two different gases at a certain temperature is equal to the square root of the inverse ratio of their masses.$  $3.5 A body has weight 20 \mathrm{~N} . How much force is required to move it vertically upward with an acceleration of 2 \mathrm{~ms}^{-2} ? (24 N)$  $ii. Inertia depends upon(a) force(b) net force(c) mass(d) velocity$  $A heat engine performs 100 \mathrm{~J} of work and at the same time rejects 400 \mathrm{~J} of heat energy to the cold reservoirs. What is the efficiency of the engine?$  $3.2 The weight of a body is 147 \mathrm{~N} . What is its mass? (Take the value of g as 10 \mathrm{~ms}^{-2} )(14.7kg)$  