How do you think you can use careful measurements to determine whether the strength of Earth's gravitational field depends on the mass of an object in the field? How can you ensure that
your methods are not influenced by previous measurements or understandings about gravity?

How does the image distance (di) of a convex lens compare with the image distance of a concave lens? a. the image distance of the convex lens is positive, and that of the concave lens is negative. b. both are negative for a virtual image. c. both are positive for a virtual image d. the image distance of the convex lens is negative, and that of the concave lens is positive.

Does work output exceed work input when a machine is used? a) yes, it does, as machines create energy. b) it depends on the type of machine used. c) no, it doesn’t, as machines are inefficient. d) no, it doesn’t, as machines cannot create energy.

Which transition by an electron will release the greatest amount of energy? oa ob oc od