Optical pyrometry is a technique used to measure temperature of very hot objects without making physical

contact with the object. This is accomplished by identifying $$max and then using Wien$$s Law. a$)$ Using Wien$$s

Law, determine $$max at $850$K$,1500$K and $5000$K$.$ b$)$ In pyrometric measurements of the Dog Star, Sirius, a $$max

of $260$nm was determined. Estimate the surface temperature of Sirius