Approximately how long have cosmic microwave background photons been traveling through space?
A) 5000 years
B) 380,000 years
C) 14 billion years
D) It depends on which direction they come from.
C) 14 billion years
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In a double slit experiment, if the separation between the two slits is 0.050 mm and the distance from the slits to a screen is 2.5 m,
find the spacing between the first-order and second-order bright fringes when coherent light of wavelength 600 nm illuminates the slits. A) 1.5 cm B) 3.0 cm C) 4.5 cm D) 6.0 cm E) 9.0 cm
Which of the following describes a star with a hydrogen-burning shell and an inert helium core?
A) It is a red giant that grows in luminosity until it dies in a planetary nebula. B) It is a subgiant that gradually grows dimmer as its hydrogen-burning shell expands and cools. C) It is a subgiant that grows in luminosity until helium fusion begins in the central core. D) It is what is known as a helium-burning star, which has both helium fusion in its core and hydrogen fusion in a shell.
Tricia puts 66 g of dry ice (solid CO2) into a 2.0-L container and seals the top. The dry ice turns to gas at room temperature (20°C). Find the pressure increase in the 2.0-L container. (One mole of CO2 has a mass of 44 g and R = 0.0821 L•atm/mol•K. Ignore the initial volume of the dry ice.)
a. 6.0 atm c. 18 atm b. 12 atm d. 2.0 atm
In a double-slit experiment using light of wavelength 486 nm, the slit spacing is 0.600 mm and the screen is 2.00 m from the slits. Find the distance along the screen between adjacent bright fringes