<span>Exothermic reaction is a chemical reaction that releases energy. This reaction releases heat energy or light .
In an endotermic reaction energy is used.
Enthaply is the heat energy change , delta H.
If the sum of the enthalpies of the reactans is greater than the products the reaction is exothermic. If the products side has a larger enthaply than the process is endothermic. So, if delta H is negative then the process is exothermic. If delta H is positive, than the process is endothermic.
Exothermic are: A+BC -> AB+C
A2+B2 -> 2AB
Endothermic are:AB+C -> AC+B
A2 + C2 -> 2AC
B2+C2 -> 2BC</span>
Stress required to cause slip on in the direction [ 1 1 0 ] is 7.154 MPa
<u>Explanation:</u>
Given -
Stress Direction, A = [1 0 0 ]
Slip plane = [ 1 1 1]
Normal to slip plane, B = [ 1 1 1 ]
Critical stress, Sc = 2.92 MPa
Let the direction of slip on = [ 1 1 0 ]
Let Ф be the angle between A and B
cos Ф = A.B/ |A| |B| = [ 1 0 0 ] [1 1 1] / √1 √3
cos Ф = 1/√3
σ = Sc / cosФ cosλ
For slip along [ 1 1 0 ]
cos λ = [ 1 1 0 ] [ 1 0 0 ] / √2 √1
cos λ = 1/√2
Therefore,
σ = 2.92 / 1/√3 1/√2
σ = √6 X 2.92 MPa = 2.45 X 2.92 = 7.154MPa
Therefore, stress required to cause slip on in the direction [ 1 1 0 ] is 7.154MPa
<span>Thermocline is a layer between
warm water from the ocean’s surface and cool water from below the ocean. In here,
the temperature decreases rapidly from the warmer layer to the colder layer. A thermocline forms due to the heat of the sun
heating the ocean’s surface. Because of the difference in density between warm
and cooler ocean water, cooler ocean water sinks and warmer ocean water floats.
This is caused due to the heat and mass transfer between particles of the
ocean. The answer is letter C. The sun’s radiation does not extend below a
certain depth; therefore, deeper ocean water is colder than surface water.</span>
Answer:
0.94 m/s^2 downwards
Explanation:
m = 70 kg, m g = 70 x 9.8 = 686 N
R = 620 N
Let the acceleration be a, as the apparent weight decreases so the elevator is moving downwards with an acceleration a.
mg - R = ma
686 - 620 = 70 x a
a = 0.94 m/s^2