This question was a concept question on my physics test.
"two identical stones are dropped from rest and feel no airresistance as they fall. stone a is dropped from height h, andstone b is dropped from height 2h. if stone a takes time t to reachthe ground, stone b will take time:
a. 2t
b. t/2
c. 4t
d. t/sqrt(2)
e. sqrt(2)*t"

Astudent is given an assignment to demonstrate diffraction. he takes a photograph of a straw in a glass of water. the straw appears bent at the water level. which best describes this example? a) this is a good example of diffraction. b) this is an example of dispersion and not diffraction. c) this is an example of refraction and not diffraction. d) this is an example of reflection and not diffraction.

What effects result when there is an impact between earth and an asteroid? check all that apply. a.massive flooding. b.extinction of many life forms.c.major earthquakes change in average global temperature.d. giant dust cloud

The two stars in a certain binary star system move in circular orbits. the first star, alpha, has an orbital speed of 36 km/s. the second star, beta, has an orbital speed of 12 km/s. the orbital period is 137 d. a) what is the mass of the star alpha? b) what is the mass of the star beta?