Judging by the density (19.3 g/ml) there's a very good chance that it could be gold.
Answer:
Explanation:
Given that:
The radius of the table r = 16 cm = 0.16 m
The angular velocity = 45 rpm
= 
= 4.71 rad/s
However, the relative velocity of the bug with turntable is:
v = 3.5 cm/s = 0.035 m/s
Thus, the time taken to reach the bug to the end is:
t = 4.571s
So the angle made by the radius r with the horizontal during the time the bug gets to the end is:
Now, the velocity components of the bug with respect to the table is:
Also, for the vertical component of the velocity 
A. Equal and opposite
For every action, there is an equal and opposite reaction
Answer:
if this surface has a higher index than in the medium where the light travels, the reflected wave has a phase change of 180º
Explanation:
When a ray of light falls on a surface if this surface has a higher index than in the medium where the light travels, the reflected wave has a phase change of 180º this can be explained by Newton's third law, the light when arriving pushes the atoms of the medium that is more dense, and these atoms respond with a force of equal magnitude, but in the opposite direction.
When the fractional index is lower than that of the medium where the reflacted beam travels, notice a change in phase.
Also, when light penetrates the medium, it modifies its wavelength
λ = λ₀ / n
We take these two aspects into account, the condition for contributory interference is
d sin θ = (m + 1/2) λ
for destructive interference we have
d sin θ = m λ
in general this phenomenon is observed at 90º
2 d = (m +1/2) λ° / n
2nd = (m + ½) λ₀
