Potential energy of spring equals K times X squared divided by 2 where X is displacement
4 times squared equals 16
choose 1st answer
Answer:
<em>a) below the observed position</em>
<em>b) directly at the observed position</em>
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Explanation:
If I'm standing on the bank of a stream, and I wish to spear a fish swimming in the water out in front of me, I would aim below the observed fish to make a direct hit. This is because the phenomenon of refraction of light in water causes the light coming from the fish is refract away from the normal as it passes into the air and into my eyes.
If I'm to zap the fish with a taser, I would aim directly at the observed fish because the laser (a form of concentrated light waves) will refract into the water, taking the same path the light from the fish took to get to my eyes.
B. By vibrations in wires or strings
Answer:

Explanation:
From the free-body diagram for the car, we have that the normal force has a vertical component and a horizontal component, and this component act as the centripetal force on the car:

Solving N from (2) and replacing in (1):

The centripetal acceleration is given by:

Replacing and solving for v:

According to periodic trends in the periodic table, the atomic radius decreases from left to right.
In period three, the element with the smallest atomic radius would be the element in the rightmost area. Protons increase as it goes to the right, which would mean they pull in electrons closer which decreases the size.
So in period 3, the element with the smallest atomic radius is Argon (Ar).