An aluminium sphere 5 cm in diameter is suspended by a fine thread inside an evacuated jar, so that is can lose heat only by radiation. The sphere's initial temperature is 100°C
and the wall of the jar is always 22°C.
a) What is the initial net rate of heat loss of the sphere?
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During a medieval siege of a castle, the attacking army uses a trebuchet to hurl heavy stones at the castle walls. if the trebuchet launches the stones with a velocity of at an angle of 50.0°, (a) how long does it take the stone to hit the ground? (b) what is the maximum distance that the trebuchet can be from the castle wall to be in range? (c) how high will the stones go? show all your work.