# (solution) 1. A lobster tank in a restaurant is 0.5 m long by 0.25 m wide by

1. A lobster tank in a restaurant is 0.5 m long by 0.25 m wide by 40 cm deep. The force of the water (in Newtons) on the bottom of the tank = on each of the larger sides of the tank = on each of the smaller sides of the tank = ( You need to compute the weight density of water to do this problem. The density of water is 1000 kg/m^{3} and the acceleration due to gravity is 9.8 m/s^2. Recall that weight is equal to mass times the acceleration due to gravity. ) 2. On August 12, 2000, the Russian submarine Kursk sank to the bottom of the sea, approximately 90 meters below the surface. Find the following at the depth of the Kursk: Water Pressure: (include units) The force (in Newtons) on a 5 meter square metal sheet held: Horizontally 90 meters below the surface = Vertically with its bottom 90 meters below the surface = (include units for each) ( You need to compute the weight density of water to do this problem. The density of water is 1000 kg/m^3 and the acceleration due to gravity is 9.8 m/s^2. Recall that weight is equal to mass times the acceleration due to gravity. ) 3. A trough is 2 feet long and 1 foot high. The vertical cross-section of the trough parallel to an end is shaped like the graph of y=x^{10} from x=-1 to x=1 . The trough is full of water. Find the amount of work in foot-pounds required to empty the trough by pumping the water over the top. Note: The weight of water is 62 pounds per cubic foot. 