The answer to number 1 is D and the answer for the second one is 2
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Answer:
1716.75 J
Explanation:
<u>Step </u><u>1</u><u>:</u> First check what we are provided with. As per given question we have:
mass (m) = 70 kg, height (h) = 2.5 m and acceleration due to gravity (g) = 9.81 m/s².
<u>Step</u><u> </u><u>2</u><u>:</u> Check what we are asked to find out.
Work done = Change in Potential energy
The stuff required to solve this question is potential energy. Using the formula: P = mgh. Where P is Potential energy, m is mass, g is acceleration due to gravity and h is height.
<u>Step</u><u> </u><u>3</u><u>:</u> Substitute the known values in the above formula.
→ P = 70 × 2.5 × 9.81
→ P = 1716.75 J
Hence, the work done against the force of gravity is 1716.75 J.
B. It contains more matter
Answer:
ΔL=0.14m
Explanation:
The period of oscillations of simple pendulum is

Here L is length of pendulum and g is acceleration due to gravity
So the length of pendulum is:

So increase in length is:
ΔL=L₂-L₁
![=\frac{T_{2}^{2}g }{4 \pi^{2} }-\frac{T_{1}^{2}g }{4 \pi^{2} }\\=\frac{g}{4 \pi^{2} }[T_2^{2} -T_1^{2} ]\\ =\frac{9.8}{4 \pi^{2}}[(1.15+0.22)^{2}-(1.15)^{2} ] \\=0.14m](https://tex.z-dn.net/?f=%3D%5Cfrac%7BT_%7B2%7D%5E%7B2%7Dg%20%7D%7B4%20%5Cpi%5E%7B2%7D%20%7D-%5Cfrac%7BT_%7B1%7D%5E%7B2%7Dg%20%7D%7B4%20%5Cpi%5E%7B2%7D%20%7D%5C%5C%3D%5Cfrac%7Bg%7D%7B4%20%5Cpi%5E%7B2%7D%20%7D%5BT_2%5E%7B2%7D%20-T_1%5E%7B2%7D%20%5D%5C%5C%20%3D%5Cfrac%7B9.8%7D%7B4%20%5Cpi%5E%7B2%7D%7D%5B%281.15%2B0.22%29%5E%7B2%7D-%281.15%29%5E%7B2%7D%20%20%5D%20%5C%5C%3D0.14m)
ΔL=0.14m