Question

Suppose it is a particularly hot summer day and you want to make some popsicles to...

Suppose it is a particularly hot summer day and you want to make some popsicles to help cool off. You fill a popsicle mold with 0.15kg of juice (suppose it is the same thermal energy as water). The juice starts out at a temperature of 30 °C and the freezer will cool it to -20 °C. a. How much heat must be removed from the popsicles in order to bring them to their final temperature. b. Draw an energy flow diagram to show the heat and work flows in this situation, and determine the minimum work needed by the freezer to remove this amount of heat from the inside of the freezer Assume the inside of the freezer remains a stable -20 °C and the outside remain 30 °C. c. If a gas fired power plat operated with 40% of efficiency, how much heat would have to be added, QH, to produced this much work? If the exhaust temperature is at 20 °C, what is the minimum TH needed to achieve this efficiency. I posted this question once and someone answered it. I solved it base on his response and showed it to my instructor who said part b and c is wrong. Can you please help me again. thank you

Science   Advanced-Physics   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
On a hot summer day you decide to make some iced tea. You brew 0.85 L...
On a hot summer day you decide to make some iced tea. You brew 0.85 L of tea at 85°C. In order to cool the tea, you add 1.1kg of ice taken from the freezer at –10°C. Treat the tea as plain water for this problem. ρw=1 kg/L (a) What is the final temperature of the tea? (b) Does all of the icesmelt? If it doesn’t all melt, how much ice is left?
1. You need design a freezer that will keep the temperature inside a -5.0 C and...
1. You need design a freezer that will keep the temperature inside a -5.0 C and will operate with a temperature inside at 5.0 C and will operate in a room with a temperature of 22.0 C. The freezer is to make 20.0 kg of ice at 0.0 C starting with water at 20.0 C. For water, the specific heat is 4190 J/kg-K, the heat of fusion is 333 kj/kg. a. How much energy must be removed from the water...
As an eager scientist on a hot summer day you wish to determine how much ice...
As an eager scientist on a hot summer day you wish to determine how much ice to buy to add to your cooler which is filled with 32 cans of soda which are warm at 82.9°F. Each can has a mass of 402 g and ideally you want the temperature of the drinks to be 40.1°F. If there is no heat lost by the cooler and ignoring any heat lost to the soda containers, how much ice needs to be...
To practice Problem-Solving Strategy 12.1 Calorimetry problems. On a hot summer day, you decide to make...
To practice Problem-Solving Strategy 12.1 Calorimetry problems. On a hot summer day, you decide to make some iced tea. First, you brew 1.50 L of hot tea and leave it to steep until it has reached a temperature of Ttea = 75.0 ∘C. You then add 0.975 kg of ice taken from the freezer at a temperature of Tice = 0 ∘C. By the time the mix reaches equilibrium, all of the ice has melted. What is the final temperature...
You want to cool 0.2 kg of coffee, initially at temperature Th = 80° C, with...
You want to cool 0.2 kg of coffee, initially at temperature Th = 80° C, with ice initially at Tc = 0° C. The specific heat of ice is about 2108 J/kg K, and its latent heat of melting is about 334, 000 J/kg. You may take the specific heats of liquid water and coffee to be the same: 4187 J/kg K. A) Assume the coffee and ice form a closed system. You want them to equilibrate at 40° C....
Your 300 mL cup of coffee is too hot to drink when served at 90°C. An...
Your 300 mL cup of coffee is too hot to drink when served at 90°C. An ice cube, taken from a −20°C freezer is used to cool your coffee to a pleasant 60°C. Assume that you have a well-insulated cup. a. Provide the statement of energy conservation for this closed “coffee-ice” system. b. What is the heat lost by coffee in bringing down the temperature to 60°C? c. How much heat is consumed in converting ice to water at 0°C?...
You place your lunch leftovers in the refrigerator. Suppose the refrigerator needs to remove 2.4280E+4 J...
You place your lunch leftovers in the refrigerator. Suppose the refrigerator needs to remove 2.4280E+4 J of thermal energy from your lunch to cool it to the temperature of the inside of the refrigerator. In the meantime, this means the refrigerator produces 3.2787E+4 J of thermal energy that it expels into the kitchen as a result. a.) What is the total work done by the compressor motor in the refrigerator? (Ignore any thermal loses due to friction in the motor.)...
You place your lunch leftovers in the refrigerator. Suppose the refrigerator needs to remove 1.4690E+4 J...
You place your lunch leftovers in the refrigerator. Suppose the refrigerator needs to remove 1.4690E+4 J of thermal energy from your lunch to cool it to the temperature of the inside of the refrigerator. In the meantime, this means the refrigerator produces 1.8957E+4 J of thermal energy that it expels into the kitchen as a result. What is the total work done by the compressor motor in the refrigerator? (Ignore any thermal loses due to friction in the motor.) What...
You place your lunch leftovers in the refrigerator. Suppose the refrigerator needs to remove 2.4820E+4 J...
You place your lunch leftovers in the refrigerator. Suppose the refrigerator needs to remove 2.4820E+4 J of thermal energy from your lunch to cool it to the temperature of the inside of the refrigerator. In the meantime, this means the refrigerator produces 3.2526E+4 J of thermal energy that it expels into the kitchen as a result. What is the total work done by the compressor motor in the refrigerator? (Ignore any thermal loses due to friction in the motor.) What...
this is a thermodynamics course We want to model energy and mass balance issues involved in...
this is a thermodynamics course We want to model energy and mass balance issues involved in strenuous exercise, for example the running of a marathon. Suppose a 70 kg marathon runner runs at an ≈8 minute/mile pace, completing the 26.2 mile race distance in 210 minutes, or 3.5 hours. a.) Physiological measurements indicate that the total power consumed by an average weight runner (70 kg) at a pace of 8 minutes/mile is about 900 kcal/hour. What is the total energy...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT