Select the two true statement about a free body diagram 1.) The arrow pointing down represents the force of gravity, and the arrow pointing up represents the force of the ground pushing back on the box

2.)The net force is unbalanced

3.)Gravitational force is pushing up on the box and the force of the ground is pushing down

4.)The net force is equal to zero

Which type of microscope would allow the viewer to see ribosomes inside a cell?

With the simplified model of the eye, what corrective lens (specified by focal length as measured in air) would be needed to enable a person underwater to focus an infinitely distant object? (be careful-the focal length of a lens underwater is not the same as in air! assume that the corrective lens has a refractive index of 1.62 and that the lens is used in eyeglasses, not goggles, so there is water on both sides of the lens. assume that the eyeglasses are 1.90

In a heat engine if 1000 j of heat enters the system and the piston does 500j of work, what is the final internal energy of the system if the inital energy was 2000 j1.write the equation2.list out your known variables 3. plug the numbers into the equations4.solve 5.write your solution statement that includes initial energy and final energy added.