The vessel has received a refrigerated...

Study

Question 1 of 205eccef9dbacbc34ba4d45e44

The vessel has received a refrigerated container loaded with 9 long tons of ice cream. The current box temperature is 31°F but has a normal set point of minus 10°F. Under ideal conditions how long will it take to pull the box temperature down to set point, if the equipment is operating properly? (Specific heat of the cargo equals 0.39 BTU/LB/°F, with a container heat gain of 6,000 BTU/hr, and a refrigeration system capacity of 3.5 tons)

Back

Question 1 of 20

5eccef9dbacbc34ba4d45e44

No comments yet

Be the first to share your thoughts!

If the question has a related picture, it will appear here.

🔍 Key Concepts

• Refrigeration ton in BTU/hr (how many BTU/hr is 1 ton of refrigeration?) • Total BTU that must be removed = mass × specific heat × temperature change, plus (or minus) heat gain over time • Converting long tons to pounds before using in BTU calculations

💭 Think About

• First, compute the total temperature change needed from 31°F down to -10°F. How many degrees is that? • Convert 9 long tons of ice cream into pounds, then calculate the total BTUs that must be removed from the cargo using the specific heat. • Find the net refrigeration capacity by converting 3.5 tons to BTU/hr and then subtracting the container heat gain. With that net capacity, how many hours are needed to remove the total BTUs?

✅ Before You Answer

• Be sure you used long tons (2,240 lb per ton), not short tons (2,000 lb). • Confirm you used 1 refrigeration ton = 12,000 BTU/hr when finding the system capacity. • Check that you added the container heat gain as a load that reduces net cooling, not as extra capacity.

👋 Hi! I'm Genie, your AI study assistant. How can I help you with this question?

Quick actions

— No credit card needed