The force of gravity is the force with which massively large objects such as the earth attracts another object towards itself. All objects of the earth exert a gravity that is directed towards the center of the earth. Therefore, the force of gravity of the earth is equal to the mass of the object times acceleration due to gravity.
<span>F = ma </span>
<span>4.9N = m (9.8 m/s^2), note that N (newtons) = kg-m/s^2 </span>
m = 0.5 kg
<span>The mass of the object is 0.5kg.</span>
Concave is not a type of mechanical wave because it doesn’t need a medium for propagation.
An acquired trait is a trait developed through learning. (:
Answer : The amount of in kilojoules released is, -5.53 kJ
Explanation :
Formula used :

where,
q = heat released = ?
c = specific heat of ethanol = 
m = mass of ethanol = 23.4 g
= final temperature = 
= initial temperature = 
Now put all the given values in the above formula, we get:


Therefore, the amount of in kilojoules released is, -5.53 kJ