Which combination of consecutive exposures would potentially overheat an anode with a maximum of 40,000 heat units?

The correct answer highlights a combination of exposures that exceeds the maximum heat capacity of the anode, which is set at 40,000 heat units (HU). In this scenario, the cumulative heat from both exposures must be assessed.

In the selected option, the first exposure alone is 49,000 HU. This value already exceeds the maximum capacity of the anode, indicating that just performing this single exposure could indeed lead to overheating the anode. Adding any additional exposure, such as the 20,000 HU from the second exposure, only compounds this problem, resulting in an even greater risk of damaging the anode due to excessive heat.

Understanding the thermal limits of radiographic equipment is crucial for preventing damage and ensuring optimal performance. Each anode can only withstand a specific amount of heat, and exceeding this threshold can lead to failure or significant wear, impacting future imaging capabilities. Estimating the total heat load from multiple exposures helps technologists avoid scenarios that may compromise the equipment's integrity.

Other combinations listed do not exceed the maximum heat capacity when calculated, which is why they would not pose a risk for overheating the anode to the same extent. Thus, they would be considered within safe operational limits.