A calorimeter of mass 60 g contains 180 g of water at 29°C. Calculate the common final equilibrium temperature of the mixture if 37.2 g of ice at - 10°C is added to it. Specific
heats are given as follows: ice = 2108 J/kg. K, calorimeter = 0.42 J/g.°C, water =
4186J/kg.°C and latent heat of fusion for ice is 333 kJ/kg.

Askydiver weighing 140 lb (including equipment) falls vertically downward from an altitude of 19,000 ft and opens the parachute after 18 s of free fall. assume that the force of air resistance, which is directed opposite to the velocity, is of magnitude 0.55|v| when the parachute is closed and is of magnitude 14|v| when the parachute is open, where the velocity v is measured in ft/s. assume that acceleration due to gravity has magnitude 32 ft/s/s; remember that weight is the product of mass and gravitational acceleration. (a) find the speed of the skydiver when the parachute opens. (b) find the distance fallen before the parachute opens. (c) what is the limiting velocity vl after the parachute opens? (d) determine how long the sky diver is in the air after the parachute opens. (e) plot the graph of velocity versus time from the beginning of the fall until the skydiver reaches the ground.

Which are advantages of renewable resources? check all that apply. renewable energy supplies are completely reliable everywhere. some renewable resources will never be used up. little or no waste is produced by renewable resource plants. electricity can be generated in large quantities. many renewable energy facilities have lower operating costs.

Explain why electric current cannot exist if a current doesn't have a voltage source.