Question

QUESTION 1 10 points Save Answer A black body ejects all radiation. Thast is why iseems to be black True QUESTION 2 10 points Save Answer Select All incorrect definitions Newton Law of oonvection states that heat loss is inversely proporsional to the change in temperature Nahural convection depends on the velocity of fluids passing over the object O Suface Geomety and fuid velooity affects the heat transfer by convection Foroed convection depends to the nature of fiow of liquids or gases

Answer 1

1 false a black body is a body which absorb and ryects as the radiations which can be sun, tini hole in sphere etc. but it is not necessary its colour will black always 50 it is not necessary that all the black body will look like black in colour 1 st is in correct Newton law of convection (or cooling) states that heat transfer is directly perportional to change in temperature theta = GA (delta T)(theta proportional delta T) 2ND is in correct natural convection do not dependent on velocity as convection takes place dve to density change (due to bouncy effect) with temperature change 3 rd correct convection depends on surface geometry and fluid velocity (in force convection) 4thy correct force convection depends on nature of flow whether it is laminar or turbulant