which of the following characteristics accurately describe passive heat sinks

I) What is a passive heat sink?

Passive radiator refers to: transfer heat to the surface of the heatsinks through internal heat transfer, and use the principle of physical expansion and contraction of heat, hot air rises, cold air descends, natural air circulation and heat radiation to take away the heatsinks surface heat.
 

Ⅱ）which of the following characteristics accurately describe passive heat sinks？

The main characteristics of passive heat sinks are as follows:
1) Passive: Passive is the main feature of passive heatsinks. Passive heatsinks do not need fans. Devices that force fluid convection such as pumps can work.

2) High reliability: Since passive heatsinks do not require fans, pumps and other devices that force fluid convection can work. Therefore, the structure is simple, and it can adapt to various harsh environments (such as desert, saline, high altitude, high temperature, vacuum, etc.)

3) No noise: (Because there is no fan and pump, there is no loud noise. But it is not silent in the absolute sense. The electronic components in the device may produce some slight whistling when running, and the noise level is large and specific. depends on the quality of the components of the device and the load used).

4) Low efficiency: Compared with other heatsinks with the same heat consumption, the passive heatsinks requires more heat dissipation area, so the passive heatsinks is larger in size and heavier in weight
 

So there is no best heatsink. We need to decide which type of heat sink to use based on factors such as device type, usage environment, power consumption, etc. If you want to know more about other heatsinks, please follow the link to read.
 

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