A marble floor appears colder than cemented floor ar winter even tough they are in same temperature

An insulated 40 ft^3 rigid tank contains air at 50 psia and 120°f. a valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 25 psia. the air temperature during this process is kept constant by an electric resistance heater placed in the tank. determine the electrical work done during this process.

Which of the the following are examples of projectile motion of both projectile motion and two dimensional motion

If a rock weighing 54 n is submerged in a liquid with a density exactly twice that of water, what will be its new apparent weight reading in the liquid?