Abosorbers and emitters?

Think about this from a thermal equilibrium viewpoint:

When a hot object is placed in a room, it will initially radiate more than it absorbs. i.e. The object will drop in temperature while the room heats up. After a while the object stop losing energy and the room stops giving up energy.

At this point the object must (on average) be absorbing radiation at the same rate as it is emitting. The room and the object are in thermal equilibrium.

Therefore when in equilibrium:

A good absorber will heat up quickly, but also lose heat at the same rate.

A poor absorber will heat up less quickly and therefore must also lose heat at the slower rate.

The key to the above is to realise that the absorption and emission radiation do not need to happen at the same wavelength.

For instance, UV will be absorbed quickly by a black surface, but radiation will be emitted at the lower infra-red wavelength. When thermal equilibrium is achieved, the incoming UV is aborbed at the same rate as the outgoing emitted IR.

A shiny reflector both absorbs and emits at the same wavelength.

That analogy kinda does make sense Thanks!

So its like if we sit in a cold room, we'll soon feel pretty cold as we emit heat; if we sit next to a heater, we'll just as soon feel warm as we quickly absorb the heat?

As an analogy, yes. because your body is hotter than the surrounding air in the cold room, you are radiating heat. You sense that heat loss as a feeling of cold.

Sitting next to a heater, your body absorbs heat and you sense that heat gain as feeling warm.

(The human body is pretty amazing.)