An anode has a maximum of 40,000 heat units. One exposure of 10,000 heat units is produced. What are the remaining heat units available?

An anode has a maximum of 40,000 heat units. One exposure of 10,000 heat units is produced. What are the remaining heat units available?

• A. 20,000
• B. 30,000
• C. 40,000
• D. 50,000

Answer: (B)

Heat units show how much heating capacity the anode has used up and how much remains before reaching the limit. If the anode can handle up to 40,000 heat units and an exposure uses 10,000, you simply subtract: 40,000 minus 10,000 equals 30,000. So 30,000 heat units are still available. The other numbers don’t fit because 20,000 would mean more heat has been used than the exposure; 40,000 would mean none has been used; 50,000 would exceed the maximum allowed.

Heat units show how much heating capacity the anode has used up and how much remains before reaching the limit. If the anode can handle up to 40,000 heat units and an exposure uses 10,000, you simply subtract: 40,000 minus 10,000 equals 30,000. So 30,000 heat units are still available. The other numbers don’t fit because 20,000 would mean more heat has been used than the exposure; 40,000 would mean none has been used; 50,000 would exceed the maximum allowed.