A hot-air balloon consists of a basket hanging beneath a large envelope filled with hot air. A typical hot-air balloon has a total mass of 514 kg, including passengers in its basket, and holds 2.62 x 10 m of hot air in its envelope. If the ambient air density is 1.24 kg/m3, determine the density (in kg/m³) of hot air inside the envelope when the balloon is neutrally buoyant. Neglect the volume of air displaced by the basket and passengers.

A block of wood with dimensions 60.0 cm × 40.0 cm × 8.0 cm floats on water with 75% of its volume below the surface of the water. While floating on water, how much mass can be placed on top of the block before it is completely submerged? The density of water is 1000 kg·m−3

A meat baster consists of a squeeze bulb attached to a plastic tube. When the bulb is squeezed and released, with the open end of the tube under the surface of the basting sauce, the sauce rises in the tube to a distance h, as the drawing shows. Using 1.013 × 105 Pa for the atmospheric pressure and 1340 kg/m³ for the density of the sauce, find the absolute pressure PB in the bulb when the distance h is (a) 0.16 m and (b) 0.08 m. (a) PB = (b) PB = i <

(a) Calculate the absolute pressure at the bottom of a fresh-water lake at a depth of 26.2 m. Assume the density of the water is 1.00 x 103 kg/m3 and the air above is at a pressure of 101.3 kPa. Pa (b) What force is exerted by the water on the window of an underwater vehicle at this depth if the window is circular and has a diameter of 31.0 cm? N