(c) A coal-fired power station generates electricity at night when it is not needed. Some of this energy is stored by pumping water up to a mountain lake. When there is high
demand for electricity, the water is allowed to flow back through turbines to generate electricity.
On one occasion, 2.05 x 108kg of water is pumped up through a vertical height of 500 m.
(i) Calculate the weight of the water.
weight =
[1]

An ideal spring has a spring constant (force constant) of 2500 n/m, is stretched 4.0 cm, how much elastic potential energy does it possess? (a) 3j (b) 0.00j (c) 1j (d) 2j (e) 4j

In a voltaic cell, electrons flow from the (positive/negative) to the (positive/negative) terminal.

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.