When the water is heated for a period of time, the temperature of the water rises gradually from an initial temperature of 25°C. When the temperature starts to rise initially, the balloon is deflated further. After heating for a period of time, the balloon becomes fully inflated as shown in Fig. 8.2. (i) Explain why the balloon deflated further when the temperature starts to rise.
(ii) Explain why the balloon becomes fully inflated as shown in Fig. 8.2.

Simple machines can a. increase force only b. decrease force only c. increase or decrease force

Light that is polarized along the vertical direction is incident on a sheet of polarizing material. only 96% of the intensity of the light passes through the sheet and strikes a second sheet of polarizing material. no light passes through the second sheet. what angle does the transmission axis of the second sheet make with the vertical?

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