Explanation:
Exothermic reaction is defined as the reaction in which release of heat takes place. This also means that in an exothermic reaction, bond energies of reactants is less than the bond energies of products.
Hence, difference between the energies between the reactants and products releases as heat and therefore, enthalpy of the system will decrease.
Whereas in an endothermic reaction, heat is supplied from outside and absorbed by the reactant molecules. Hence, enthalpy of the system increases.
As water acts as a coolent and when fuel rods in a nuclear reactor are immersed in it then heat created by coolent is absorbed by water and then it changes into steam.
Since, absorption of heat occurs in the nuclear reactor. Therefore, it is an endothermic reaction.
Thus, we can conclude that nuclear reactors use fuel rods to heat water and generate steam. This process is endothermic.
Answer:


Δd = 
Explanation:
As
, when the car is making full stop,
.
. Therefore,

Apply the same formula above, with
and
, and the car is starting from 0 speed, we have

As
. After
, the car would have traveled a distance of

Hence 
As
we can simplify 
After t time, the train would have traveled a distance of 
Therefore, Δd would be 
<u>We are Given:</u>
Mass of the block (m) = 500 grams or 0.5 Kg
Initial velocity of the block (u) = 0 m/s
Distance travelled by the block (s) = 8 m
Time taken to cover 8 m (t)= 2 seconds
Acceleration of the block (a) = a m/s²
<u>Solving for the acceleration:</u>
From the seconds equation of motion:
s = ut + 1/2* (at²)
<em>replacing the variables</em>
8 = (0)(2) + 1/2(a)(2)²
8 = 2a
a = 4 m/s²
Therefore, the acceleration of the block is 4 m/s²