A) Energy is absorbed in the reaction.
Such reactions are called endothermic reactions.
Answer:
39.240 W
Explanation:
Let's start by calculating the work done by the engine. We can assume that it is the same work done by the weight of the object to bring it from 40m to the surface: as much energy it takes to bring it up, the same ammount it takes to bring it down. Said work is 
At this point we can simply apply the definition of power, that is
, to get the power of the engine is 
The elastic potential energy (Ep) is given by

Data:
Ep = ? (Joule)
k = 20 N/m
x (displacement) = 0.20 m
Solving:




For this problem, we use the Coulomb's law written in equation as:
F = kQ₁Q₂/d²
where
F is the electrical force
k is a constant equal to 9×10⁹
Q₁ and Q₂ are the charge of the two objects
d is the distance between the two objects
Substituting the values:
F = (9×10⁹)(-22×10⁻⁹ C)(-22×10⁻⁹ C)/(0.10 m)²
F = 0.0004356 N
Answer:
1362000 kgm/s
Explanation:
So the total mass combination of the plane and the people inside it is
M = 35000 + 160*65 = 45400 kg
After 15 seconds at an acceleration of 2 m/s2, the plane speed would be
V = 2*15 = 30 m/s
So the magnitude of the plane 15s after brakes are released is
MV = 45400 * 30 = 1362000 kgm/s