Answer:
In free fall, mass is not relevant and there's no air resistance, so the acceleration the object is experimenting will be equal to the gravity exerted. If the object is falling on our planet, the value of gravity is approximately 9.81ms2 .
Answer:
<em>113.4 J</em>
Explanation:
<u>Elastic Potential Energy</u>
Is the energy stored in an elastic material like a spring of constant k, in which case the energy is proportional to the square of the change of length Δx and the constant k.

The spring has a natural length of 0.7 m and a spring constant of k=70 N/m. When the spring is stretched to a length of 2.5 m, the change of length is
Δx = 2.5 m - 0.7 m = 1.8 m
The energy stored in the spring is:

PE = 113.4 J
Answer:
f = 1 m
Explanation:
The magnification of the lens is given by the formula:

where,
M = Magnification = 4
q = image distance = 5 m
p = object distance = ?
Therefore,

Now using thin lens formula:

<u>f = 1 m</u>
I think it is but 1. Element symbol
I believe the answer is C