Answer:
The type of light and the material of lenz.
Explanation:
1) As the investigation is based on how the thickness of a lens effect the other variable. Thickness of the lenz is independent variable. So Lidia has to experiment with the different thicknesses in order to find the effect on dependent variable.
2) As the investigation is based to find the point where the beam of light is focused. It's a dependent variable and Lidia has no control over it. So the only thing she can do is to measure and observe how it respond to the changes in independent variable.
3) For conclusion, she has to make sure that the other variables are not effecting the output or results that is the beam point where the light is focused. So she must have to kept constant the type of light and material of lenz otherwise she won't be able to discriminate the effect of thickness of lenz from other causes.
Answer:
(a). The strength of the magnetic field is 0.1933 T.
(b). The magnetic flux through the loop is zero.
Explanation:
Given that,
Radius = 11.9 cm
Magnetic flux 
(a). We need to calculate the strength of the magnetic field
Using formula of magnetic flux





Put the value into the formula


(b). If the magnetic field is directed parallel to the plane of the loop,
We need to calculate the magnetic flux through the loop
Using formula of flux

Here, 


Hence, (a). The strength of the magnetic field is 0.1933 T.
(b). The magnetic flux through the loop is zero.
The answer is A. The kinetic energy
<em>The correct answer is option</em><em> B.</em> The maximum height that can be reached by the stone is determined as 11.5 m.
<h3>
Maximum height attained by the stone </h3>
The maximum height attained by the stone when it is a 2/3 of its total height is calculated as follows;
v² = u² - 2gh
where;
- v is final velocity at maximum height, v = 0
- u is initial velocity
- g is acceleration due to gravity
0 = u² - 2gh
2gh = u²
h = u²/2g
h = (15²)/(2 x 9.8)
h = 11.48 m
h = 11.5 m
Thus, the maximum height that can be reached by the stone is determined as 11.5 m
Learn more about maximum height here: brainly.com/question/12446886
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