If the Sun's temperature were much colder and it were much smaller Earth would no longer support human life
That's an opinion, but if you meant temperature-wise, the answer would be smaller stars because of the gas and pressure.
Because the sun's light and heat is blocked during a solar eclipse, the air gets cooler.
In temperature? Probably more people might move there seeking a cooler climate. But since that is not likely to happen anytime soon, probably nothing will come of any kind of temperature change for this city.
About one degree cooler by the equator and five degrees cooler by the ice caps.
it would expand
If the stomata were smaller then CO2 would diffuse into the cell less rapidly.
In terms of absolute magnitude, a larger hotter star will necessarily be more luminous than a smaller cooler star. However, if a smaller cooler star is much closer to us than a larger hotter star, it may appear to be brighter. None of this has anything to do with the HR diagram.
you would turn the temperature down for cooler air temperatures in a car, in a house the air temperature coming out the vents does not change based on the thermostats set point
your eye would explode
The sun would be cooler
Celsius
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