The force applied to the spring is the weight of the object that compresses it, so it is equal to:

Because of this force, the spring compresses by

. Using Hook's law,

,
since we know the intensity of the force (the weight W) and the compression of the spring, x, we can find k, the spring constant:
The moment of a couple is Force × perpendicular distance from the arm of the line of action
so the arm of the couple= moment of couple/force=8.5/34=0.25m
the arm is 0.25m
Answer:
1) Coal is a natural resource, so is wood, wind energy, soil, salt, fluorite, water, and copper
2) Solar energy, natural gas, and wind energy are all renewable
3) Salt is non - renewable as is synthetic diamonds and plastic
4) I think it would be number
5) Based on their mineral, chemical, and textural composition
Explanation:
Hope this helps :)
Answer:

Explanation:
The relationship between the refractive index and the critical angle is given as follows:

where,
η = refractive index = 1.67
θc = critical angle =?
Therefore,

