Physics Past Questions and Answers

A hydraulic press has a large circular piston of radius 0.8m and a circular plunger of radius 0.2m. A force of 500N is exerted by the plunger. Find the force exerted on the piston

A 8000N
B 4000N
C 2000N
D 31N

Question 12:

The volume of an air bubble increases from the bottom to the top of a lake at constant temperature because

A Atmospheric pressure acts on the surface of the lake
B Pressure increases with depth
C Density remains constant with pressure
D The bubble experiences an upthrust

Question 13:

Temperature is the measure of the

A Quantity of heat transferred into the molecules of an object
B Mean kinetic energy of the molecules of the object
C Kinetic energy of any individual molecule of the substance
D Amount of work done by the molecules of the object

Question 14:

A rectangular metal block of volume 10^-6m³ at 273k is heated to 573k. If its coefficient of linear expansion is 1.2 x 10^-5k^-1, the percentage change of it volume is

A 1.5%
B 1.1%
C 0.4%
D 0.1%

Question 15:

A piece of wood floats inside water at room temperature with a fraction of it above the liquid surface. As the temperature of the water is raised, the part of the wood above the liquid will

A Decrease because the density of water decreases with temperature
B Increase because the density of water decreases with temperature
C Decreases because the density of water increases with water temperature
D Increase because the density of water increases with temperature