Geometric and Physical Optics
What effect does adding more capacitors in parallel have on the total capacitance of an electrical circuit?
The total capacitance decreases.
The total capacitance increases.
The total capacitance stays the same.
The total capacitance increases but less than proportionally.
If a plane electromagnetic wave is traveling in a vacuum and then enters a medium with a higher refractive index, what happens to the speed of the wave within that medium?
The speed remains unchanged.
The speed decreases.
The wave immediately reflects back into the vacuum.
The speed increases.
What is the SI unit of frequency for electromagnetic waves?
Newton (N)
Ampere (A)
Joule (J)
Hertz (Hz)
When sunlight passes through Earth's atmosphere and heats its surface, which process describes how this heat is distributed around our planet?
Primarily by convection as warm air rises and cool air sinks creating atmospheric circulation patterns.
Mainly by radiation with Earth emitting infrared light absorbed evenly across its terrain.
Predominantly by conduction where molecules directly transfer their kinetic energy to neighboring molecules in sequence around Earth’s surface.
Largely by electromagnetic induction resulting in current flows within Earth's magnetic field causing heating effects globally.
In what way did Heinrich Hertz's experiments affirm Maxwell's theories about electromagnetic waves?
His work on piezoelectric crystals offered insights into ferroelectricity phenomena unrelated but complementary findings made concurrently.
He showed that electric charges could be transported through vacuum via invisible 'ether,' proving existence outside laboratory conditions.
He demonstrated that radio waves are reflected by metallic surfaces similarly to how light is reflected by mirrors.
By measuring shifts in wavelength under varying static electric fields, he provided quantitative evidence supporting special relativity years ahead.
In what way does increasing frequency affect electromagnetic waves traveling through vacuum?
It increases both their speed and energy proportionally.
It reduces their amplitude but increases their speed simultaneously.
It decreases their wavelength without affecting their speed or energy.
It increases their energy but does not change their speed.
What type of heat transfer mechanism primarily warms your hands when holding them near a campfire?
Conduction, as direct contact allows heat flow from fire to hands.
Evaporation, as moisture in your hands absorbs heat and evaporates.
Convection, due to warm air rising from the fire towards your hands.
Radiation, because heat is transferred via electromagnetic waves emitted by the fire.

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What happens to the current through an ideal resistor when the voltage across it is halved?
The current quadruples.
The current is also halved.
The current remains unchanged.
The current doubles.
If the speed of light in a vacuum were to decrease, what would be the most immediate effect on the energy (E) of photons emitted by an LED light with a fixed frequency (f)?
E decreases because energy is directly proportional to frequency and inversely proportional to wavelength, which increases if light's speed decreases.
E is unpredictable without additional information about how other fundamental constants are affected.
E remains unchanged because energy depends only on Planck's constant and the unaltered frequency.
E increases due to the increased interaction time between photons and electrons within the LED material.
Which term refers to the angle between the direction of an electromagnetic wave's electric field vector and the direction of propagation?
Polarization angle
Incidence angle
Refraction angle
Diffraction angle