Physics Past Questions and Answers

A cube of side 10cm and mass 0.5kg floats in a liquid with only \(\frac{1}{5}\) of its height above the liquid surface. What is the relative density of the liquid?

The distance between the fixed points of a centigrade thermometer is 20cm. What is the temperature when the mercury level is 4.5cm above the lower mark?

The length of a side of a metallic cube at 20<sup style='font-size: smaller;'>o</sup>C is 5.0cm. Given that the linear expansivity of the metal is 4.0 x 10<sup style='font-size: smaller;'>-5</sup>k<sup style='font-size: smaller;'>-1</sup>, find the volume of the cube at 120<sup style='font-size: smaller;'>o</sup>C .

As a result of air at the top of a barometer, the height of the mercury column is 73.5cm when it should be 75.0cm; the volume of the space above the mercury is 8.0cm<sup style='font-size: smaller;'>3</sup>. Calculate the correct barometer height when the barometer reads 74.0cm and the volume of the space above the mercury is 6.0cm<sup style='font-size: smaller;'>3</sup>.

Hot water is added to three times its mass of water at 10<sup style='font-size: smaller;'>o</sup>C and the resultant temperature is 20<sup style='font-size: smaller;'>o</sup>C. What is the initial temperature of the hot water?