Hot air balloon rises because a) molecules become lighter when heated b) molecules move faster and farther apart when heated c) molecules are less attracted by gravity when heated d) molecules become charged and repel each other when heated

The potential in a region between x = 0 and x = 6.00 m is v = a + bx, where a = 14.0 v and b = -7.30 v/m.

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.

Assume this car is driven off a cliff . how many arrows of force need to be drawn in the free body diagram? assume no air resistance -five -one -three -four