Capacitors A and B are identical. Capacitor A is charged so it stores 4 J of energy and capacitor B is uncharged. The capacitors are then connected in parallel. The total stored energy in the capacitors is now:
A. 16 J
B. 8 J
C. 4 J
D. 2 J
E. 1 J

B. 8 J

Explanation:

From the question,

The voltage in each of the identical capacitor is given as

W = 1/2CV² Equation 1

Where Q = charge, V = potential difference, C = Capacitance of the capacitor.

make V the subject of the equation

V = √(2W/C) Equation 2

Given:  W = 4 J,

Substitute into equation 2 and find the value of V in terms of C

V = √(8/C)

Since both capacitor were connected in parallel,

The total potential difference = potential difference of on of the capacitor = √(8/C)

Total capacitance = 2C.

using equation 1,

W = 1/2(√(8/C))²×2C

W = 8 J.

Hence the right option is B. 8 J

absorption lines are where light has been absorbed by the atom thus you see a dip in the spectrum whereas.

emission spectra have spikes in the spectra due to atoms releasing photons at those wavelengths.

explanation:

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.