Answer / Explanation:
To properly answer this question, let us define what a grain boundary is:
A grain boundary is the interface between multiple grains or crystals in a poly-crystalline material. They could also be refereed to as defects in the crystal structure and tend to decrease the electrical and thermal conductivity of structures.
Now, if we refer back to the question asked,
(a) The surface energy is grater than the grain boundary energy because surface atom have fewer bonds than atom along a grain boundary.
Consequentially, the lower the number of bonds formed, the higher the energy
(b) A higher angle grain boundary has higher misalignment and hence greater disruption of bonds (lesser number of bonds) than a small angle grain boundary. Therefore, a high angle grain boundary has higher energy.
Answer:
As Per Provided Information
Velocity of wave v is 10m/s
These ocean wave passes a stationary point every 5 s ( It's time period)
First we calculate the frequency of ocean wave .
<u>Using</u><u> Formulae</u>

here
v is the velocity of wave .

Now calculating the wavelength of the wave .
<u>Using </u><u>Formulae </u>

Substituting the value and we obtain

<u>Therefore</u><u>,</u>
- <u>Wavelength </u><u>of </u><u>the </u><u>wave </u><u>is </u><u>100 </u><u>metres</u><u>.</u>
F = applied force on the wheelbarrow in forward direction = 600 N
f = frictional force pushing in backward direction of wheelbarrow = ?
m = mass of the wheelbarrow = 28 kg
Since wheelbarrow moves forward at a constant velocity
a = acceleration of the wheelbarrow in forward direction = 0 m/s²
force equation for the motion of wheelbarrow in forward direction is given as
F - f = ma
inserting the above values in the formula
600 - f = (28) (0)
600 - f = 0
f = 600 N
hence the frictional force comes out to be 600 N
<span>atoms are made of particles that have a negative charge.</span>