Cut a 7-inch-diameter a circle out of card stock. Draw a spiral on the circle as shown. Next, use the scissors to cut along the lines you drew starting on the outside and ending in the center. Use the hole punch or
scissors to make a hole at the middle of the spiral and attach the thread with a knot. Tie the other end of
the thread loosely around the center of the stick so you can suspend the spiral in the air. Fill the pot with 2
inches of water. Heat the water until it boils, and then turn off the heat source. Let the pot sit for 4
minutes. Holding the ends of the stick with the spiral attached, position the bottom of the spiral right
above the top of the pot so it's not touching the water. Describe what happens.

An internally reversible refrigerator has a modified coefficient of performance accounting for realistic heat transfer processes of where qin is the refrigerator cooling rate, qout is the heat rejection rate, and is the power input. show that copm can be expressed in terms of the reservoir temperatures tc and th, the cold and hot thermal resistances rt,c and rt,h, and qin, as where rtot rt,c rt,h. also, show that the power input may be expressed as 1.39 a household refrigerator operates with cold- and hot-temperature reservoirs of tc 5 c and th 25 c, respectively. when new, the cold and hot side resistances are rc,n 0.05 k/w and rh,n 0.04 k/w, respectively. over time, dust accumulates on the refrigerator’s condenser coil, which is located behind the refrigerator, increasing the hot side resistance to rh,d 0.1 k/w. it is desired to have a refrigerator cooling rate of qin 750 w. using the results of problem 1.38, determine the modified coefficient of performance and the required power input w under (a) clean and (b) dusty coil conditions. internally reversible refrigerator qout qin w high-temperature reservoir low-temperature reservoir th th,i tc,i tc high-temperature side resistance low-temperature side resistance w qin th tc qinrtot tc qinrtot copm tc qinrtot th tc

Determine el momento angular de un rueda de 3000g moviendose a 10m/s con un radio de giro de 400cm

Which describes increasing the efficiency of energy resource