At one stage during its birth, the protosun had a luminosity of 1000 L_sun and a surface temperature of about 1000 K. At this time, what was its radius? Express your answer in three ways: as a multiple of the Sun’s current radius, in kilometers, and in AU.

Using T = 5800k, we have that,

R/R.=( T/T.)^2=L/L.= (5800/1000)^2= 1.1 ×10^3. Of the suns radius.

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.