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As the oil is heated, heat energy is transfered around the oil via conduction and convection currents. the overall temperature of the oil rises and because its surrounding the pericarp it will heat the pericarp evenly (all around) Popcorn directly over the hotspots will be shifted around when the pot is shaked. The pot has a lid over it to prevent heated hair to escape via convection. This aids the oil in losing less heat thus making the popcorn popping more efficient.

> > > > > **The thermodynamic efficiency, e, of heat energy flow to carry out a process is defined as:** > > e = what you get / what you pay for > > **In the case of popping corn, the energy efficiency is a value for the joules of energy needed to produce a bowl of popcorn divided by the heat energy you must actually purchase to carry out the operation. The latter term includes the heat energy wasted into the room by inefficiencies of heat transfer.**
 * 1) ** Evaluate the heat energy required for using conventional stove and microwave oven to popcorn. Use the chart given below to complete the calculations. Show your calculated result for each yellow box. **
 * 1) ** Calculate the actual electric energy consumption for both methods. You may use the chart below to help you. **
 * 1) Calculate the efficiency of each method:


 * 1) Calculate the energy wasted (J) in each method.


 * 1) Time that a 100 W bulb could burn if all the wasted energy is used for that purpose.

ANSWER!: [|__Popcorn (Tan Boon Yu).xlsx__]

> Microwave - As radiant energy is emitted by the cooking components in the microwave oven, it doesn't simply travel to the popcorn. the revolving dish in the microwave will also absorb some of this energy and heat up. some of this energy can also escapes the oven via the glass pane on the door of the oven. the metal internal surfaces of the oven probably do not have an emissitivity value of absolute 0 so it will absorb some of this radiant energy and heat up too. > conventional stove-top popper - As this method involves the use of an open flame, heat may be lost to the surroundings before the pot even heats up. More energy is required to heat the oil in the pot and the pot itself before the popcorn can start popping. the convenience package used in the microwave probably was air tight as such pressure within the bag would've aided the process of popping the corn, making it more efficient. **
 * 1) **Discuss your findings and reflections in part (4) & (5). Also discuss where did the heat energy go? (Is it really wasted?)
 * 1) **Research shows that in developed countries like Singapore, electricity generation is only 34% efficient with respect to the energy content of the fuels burned, compared with the electrical energy delivered to the home. Do a calculation of "overall" or "global" efficiency taking this indirect energy loss into account. Also calculate how many joules of energy must be obtained from natural resources to pop corn.**