Im pretty sure the answer is c; velocity is usually measure by a vector :)
Answer:
c. absorbs all the energy that strikes it.
Explanation:
<em>An ideal black body is an object that absorbs every light energy (irrespective of the wavelength and direction) that strikes it without reflecting any in return. </em>
<em>Such objects or bodies usually appear perfectly black and will only emit radiation when heated to a very high temperature.</em>
Newton's 2nd law of motion says
Net force = (mass) x (acceleration)
Plug in the things you know, and you have
80 N = (20 kg) x (acceleration)
Divide each side by (20 kg) :
80N / 20kg = acceleration
acceleration = 4 m/s²
For the answer to the question above,
<span>Q = amount of heat (kJ) </span>
<span>cp = specific heat capacity (kJ/kg.K) = 4.187 kJ/kgK </span>
<span>m = mass (kg) </span>
<span>dT = temperature difference between hot and cold side (K). Note: dt in °C = dt in Kelvin </span>
<span>Q = 100kg * (4.187 kJ/kgK) * 15 K </span>
<span>Q = 6,280.5 KJ = 6,280,500 J = 1,501,075.5 cal</span>