<span>Since there is no friction, conservation of energy gives change in energy is zero
Change in energy = 0
Change in KE + Change in PE = 0
1/2 x m x (vf^2 - vi^2) + m x g x (hf-hi) = 0
1/2 x (vf^2 - vi^2) + g x (hf-hi) = 0
(vf^2 - vi^2) = 2 x g x (hi - hf)
Since it starts from rest vi = 0
Vf = squareroot of (2 x g x (hi - hf))
For h1, no hf
Vf = squareroot of (2 x g x (hi - hf))
Vf = squareroot of (2 x 9.81 x 30)
Vf = squareroot of 588.6
Vf = 24.26
For h2
Vf = squareroot of (2 x 9.81 x (30 – 12))
Vf = squareroot of (9.81 x 36)
Vf = squareroot of 353.16
Vf = 18.79
For h3
Vf = squareroot of (2 x 9.81 x (30 – 20))
Vf = squareroot of (20 x 9.81)
Vf = 18.79</span>
Average speed=total distance travelled/time
Explanation:
A wave having a frequency of 200 Hz means that 200 such waves pass through a point per second.
<h3>
Answer:</h3>
<h3>
Explanation:</h3>
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λ=500 nm = 500·10⁻⁹ m
c=3·10⁸ m/s
h=6,63·10⁻³⁴ J·s = 4,14·10⁻¹⁵ eV·s
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E - ?
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I would say A. because during the solar eclipse you cannot see the suns Photosphere at all, and the corona is the light that emits around the moon during the eclipse.
