Which type of scanner uses X-rays, and why? A Computer scanners, because X-rays release electrons via the
photoelectric effect
B. Bar-code scanners, because X-rays are low-energy waves, making
it safe for the machine operators
c. Security baggage scanners, because X-rays either pass through or
are absorbed by the objects in the baggage, creating an image of
the objects
D. Bar-code scanners, because X-rays produce a pattern of reflected
light when they shine on a pattern of black-and-white images

Abird flies directly overhead from where you stand at an altitude of 300.0 m and at a speed horizontal to the ground of 20.0 m/s. the bird has a mass of 2.0 kg. the radius vector to the bird makes an angle \thetaθ with respect to the ground. the radius vector to the bird and its momentum vector lie in the xyxy-plane. what is the bird’s angular momentum about the point where you are standing?

Air enters a gas turbine with two stages of compression and two stages of expansion at 100 kpa and 17°c. this system uses a regenerator as well as reheating and intercooling – the intercooler returns the air to the inlet temperature. the pressure ratio across each compressor is 4 ; 300 kj/kg of heat are added to the air in each combustion chamber; and the regenerator operates perfectly while increasing the temperature of the cold air by 20°c. determine the system’s thermal efficiency. assume isentropic operations for all compressor and the turbine stages and use constant specific heats at room temperature. (0.378)

If the area of a square has increased by a factor of 16, by how much has each side increased?