Answer:
(1) Resonance
Explanation:
Resonance is the process whereby a system is set into vibration due to the vibration of a nearby system with larger amplitude. The frequency at which this vibration takes place is called the resonant frequency.
It is a phenomenon of amplification that occurs when the frequency of a periodically applied force is in harmonic proportion to the natural frequency of the system on which it acts.
The missing question is: how many photons are produced per second?
Answer:

Explanation:
The energy of a photon is given by

where
h is the Planck constant
c is the speed of light
is the wavelength of the photon
In this problem, the photons have wavelength
, so each photon has an energy of

The total energy emitted by the bulb in 1 second is
E = 100 J
Therefore, the number of photons emitted per second is

Answer: Voltage is the same across each component of the parallel circuit. The sum of the currents through each path is equal to the total current that flows from the source. You can find total resistance in a Parallel circuit with the following formula: 1/Rt = 1/R1 + 1/R2 + 1/R3 +.
Hope this helps!
Answer:
<em>D. The total force on the particle with charge q is perpendicular to the bottom of the triangle.</em>
Explanation:
The image is shown below.
The force on the particle with charge q due to each charge Q = 
we designate this force as N
Since the charges form an equilateral triangle, then, the forces due to each particle with charge Q on the particle with charge q act at an angle of 60° below the horizontal x-axis.
Resolving the forces on the particle, we have
for the x-component
= N cosine 60° + (-N cosine 60°) = 0
for the y-component
= -f sine 60° + (-f sine 60) = -2N sine 60° = -2N(0.866) = -1.732N
The above indicates that there is no resultant force in the x-axis, since it is equal to zero (
= 0).
The total force is seen to act only in the y-axis, since it only has a y-component equivalent to 1.732 times the force due to each of the Q particles on q.
<em>The total force on the particle with charge q is therefore perpendicular to the bottom of the triangle.</em>
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