The correct answer is
C. reduce the friction between its moving parts
In fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.
Answer: Force = 81 N
Explanation:
from Columbs law,
F = k(q1*q2)/r²
k = 9 x 10^9 Nm²/C²
F = (9 x 10^9)x (0.9x10^-5 x 2.5x10^-4)/(0.5)²
F = 81 Newtons
That would be 0 degrees Celsius aka the melting point of water.... If you look at the diagram I attached you notice that at 0 degrees Celsius it is flat, this is because much heat is needed at this point for water to rise to 1 degree... It is the same for the boiling point (100)
Hope this helps! (If correct, please rank as brainliest answer) :)
Answer:
Explanation:
We shall apply law of refraction which is as follows
sin i / sinr = μ , where i is angle of incidence , r is angle of refraction and μ is refractive index
here i = θa = 22.5°
r = θb
μ = 1.77
sin22.5 / sinθb = 1.77
.3826 / sinθb = 1.77
sinθb = .216
θb = 12.5 °.