Physics Answers

. A piece of gold is suspended from a string and then completely immersed in a container of mercury. The volume of gold is 300cm3 and its density is 19.3 X 103 kg/m3 . Calculate the tension in the string before and after the gold is immersed in mercury.

In a car lift used in a service station, compressed air exerts a force on a small piston having a radius of 1.5 cm. This pressure is transmitted to a second piston of radius of 6.75 cm. What force must the compressed air exert in order to lift a car weighing 17,750 Newton’s? What air pressure will produce this force?

A king orders a gold crown having a mass of .5 kilograms. When it arrives from the metal smith, the volume of the crown is found to be 185 cm3 . Is the crown made of gold?

A small ingot of shiny gray metal has a volume of 25 cm3 and a mass of 535 grams. What is the metal?

Calculate the mass of a solid iron sphere that has a diameter of 3.0 cm.

A piece of aluminum is suspended from a string and then completely immersed in a container of water. The mass of the aluminum is 1 kilogram and its density is 2.7 X 103 kg/m3 . Calculate the tension in the string before and after the aluminum is immersed in water.

Calculate the total force exerted on the outside of a circular submarine window of diameter 30-cm at a depth of 1200 meters.

in young's two-slit experiment using light of wavelength 6.0×10^-7m, the slits were 0.40mm apart and the distance of the slits to the screen was 1.20m find the separation of the fringes. what is the angle in radians subtended by a central pair of bright fringes at the slit? 

The rubber cord of a catapult has a cross sectional area 1.0mm^2 and a total unstretched length 10.0cm. It I stretched to 12.0cm and then released to project a missile of mass 5.0g. From energy considerations, or otherwise, calculate the velocity of projection, taking the young modulus for the rubber as 5.0x10^8 Pa. State the assumptions made in your calcukation

A string with a length of 3 m has two adjacent resonances at frequencies 112 Hz and 140 Hz. Determine the speed of the waves on the string vibrating at 140 Hz.