Sound waves moves down a hall past an open doorway. Waves of which wavelength would have the hardest time diffracting through the doorway into the room?

Which of the following is another term for a planned economy

Relate the real life phenomenon with each branch physics; 1; mechanics 2; heat 3; sound 4; light(optics) 5; electricity& magnetism 6; atomic physics 7; nuclear physics 8; plasma physics 9; geophysics

Why would an orange roll of your cafeteria tray if you stopped suddenly