An electron is negatively charged.
The lower the frequency the lower the pitch sound.
Answer:
Second Choice.
Explanation:
Jack's Power = W/t
Jill's Power = 2W/(0.5)*t
2/0.5 = 4
Jill's Power = 4*W/t
Jill's Power is 4 times greater than Jack's
Second Choice
Answer: C.
Explanation:
For a parallel-plate capacitor where the distance between the plates is d.
The capacitance is:
C = e*A/d
You can see that the distance is in the denominator, then if we double the distance, the capacitance halves.
Now, the stored energy can be written as:
E = (1/2)*Q^2/C
Now you can see that in this case, the capacitance is in the denominator, then we can rewrite this as:
E = (1/2)*Q^2*d/(e*A)
e is a constant, A is the area of the plates, that is also constant, and Q is the charge, that can not change because the capacitor is disconnected.
Then we can define:
K = (1/2)*Q^2/(e*A)
And now we can write the energy as:
E = K*d
Then the energy is proportional to the distance between the plates, this means that if we double the distance, we also double the energy.
B. The velocity of the second flight is negative compared to the speed.
