Water is boiled in a 1-l coffee maker with an immersion-type electric heating element at atmospheric pressure. it was observed that ½-l has evaporated in 13 min once boiling starts. a) if the heating element is rated based on power required to evaporate water, determine the rating of the heating element. b) for the same heating element, how long will it take to raise the 1-l temperature from 18 oc to boiling point at the same atmospheric pressure? take liquid water density air = 1000 kg/m3 & specific heat cpwater = 4.18 kj/(kg. ok).

Arod of some material 0.20 m long elongates 0.20 mm on heating from 21 to 120°c. determine the value of the linear coefficient of thermal expansion [in (degrees c)^-1] for this material.

Arotating space station is said to create “artificial gravity”—a loosely-defined term used for an acceleration that would be crudely similar to gravity. the outer wall of the rotating space station would become a floor for the astronauts, and centripetal acceleration supplied by the floor would allow astronauts to exercise and maintain muscle and bone strength more naturally than in non-rotating space environments. if the space station is 200 m in diameter, what angular velocity would produce an “artificial gravity” of 9.80 m/s^{2} 2 at the rim?

Two pans of a balance are 24.1 cm apart. the fulcrum of the balance has been shifted 1.33 cm away from the center by a dishonest shopkeeper. by what percentage is the true weight of the goods being marked up by the shopkeeper? assume the balance has negligible mass. answer in units of %.