The answer is Air Resistance
Answer: B. Concrete
Explanation:
Let N = reacting force pressing the bodies in context together (units in Newtons),
The question stated that the force pressing the two mounted/stacked objects together is equal to the weight of the object on top.
We need to start by finding the weight of the piece of wood.
friction is given by
f = μN
The value of f is 22.5,
and from the chart reference the coefficient of friction between wood and stone, μ is 0.30.
22.5 = 75. 0.30
Putting the values into the equation: 22.5 = 0.30N.
Divide both sides by 0.30 to find the value of N:
N= 22.5/0.3 = 75
Now that the piece of wood will be placed on another surface, its weight of 75 Newton is the force pressing the two bodies together.
To determine the new surface, you should find the new coefficient of friction by using the new value of the force of friction given 46.5:
46.5 = µ(75).
Divide both sides by 75 to isolate μ.
The refer chart also indicates that the coefficient of friction equals 0.62 between wood and concrete, so the new surface corresponding to 0.62 is the concrete, which is (B).
<span>So when two metals of equal mass but different heat capabilities are subjected to same heat quantity, the metal with higher heat capacity have the small temperature change. Heat supplied is determined as heat capacity of the metal times the change in temperature.</span>
<span>1.0 gram (g) of electrons would contain 10^27 electrons
Electrons have an electric charge of −1.602×10−19 coulomb
so total charge of 1 g electrons = -1.602 x 10^-19 x 10^27 = -1.602 x 10^8</span>