<h2>Explanation:</h2><h3>3. </h3>
When light bounces back, it is <em>reflected</em>. (That's why you see your <em>reflection</em> in a mirror.) When light is bent from the path it is taking, it is <em>refracted</em>. The only answer choice that makes correct use of these terms is the third choice:
- Part of the ray is <em>refracted</em> into ray B; part of the ray is <em>reflected</em> as ray R.
_____
<h3>4.</h3>
The index of refraction is the ratio of the sine of the angle of incidence to the sine of the angle of refraction. Both angles are measured from the normal to the surface. The angle of refraction here is 12.5° less than the angle of incidence, 44°, so is 31.5°. Then the index of refraction of the medium is ...
n = sin(44°)/sin(31.5°) = 0.69466/0.52250 = 1.3299 ≈ 1.33
- none of the offered choices is correct. The closest is 1.34.
Answer:
12.32 m/s
Explanation:
Using the formula of maximum height of a projectile,
H = u²sin²Ф/2g................... Equation 1
Where H = maximum height, u = initial velocity, Ф = angle of projection, g = acceleration due to gravity
make u the subject of the equation
u = √(2Hg/sin²Ф)............ Equation 2
Given: H = 2.3 m, Ф = 33°, g = 9.8 m/s²
Substitute into equation 2
u = √[(2×2.3×9.8)/sin²33°]
u =√ [45.08/(0.545)²]
u = 45.08/0.297
u = √(151.785)
u = 12.32 m/s
Answer:
a) Wavelength of the ultrasound wave = 0.0143 m <<< 3.5m, hence its ability is not limited by the ultrasound's wavelength.
b) Minimum time difference between the oscillations = Period of oscillation = 0.00952 ms
Explanation:
The frequency of the ultrasound wave = 105 KHz = 105000 Hz. The speed of ultrasound waves in water ≈ 1500 m/s. Wavelength = ?
v = fλ
λ = v/f = 1500/105000 = 0.0143 m <<< 3.5m
This value, 0.0143m is way less than the 3.5m presented in the question, hence, this ability is not limited by the ultrasound's wavelength.
b) Minimum time difference between the oscillations = The period of oscillation = 1/f = 1/105000 = 0.00000952s = 0.00952 ms
Hope this helps!
Something stopped the force and was able to recreate the same amount of force to send it back to her. Example: A pole
Answer:
If the radio wave is on an FM station, these are in Megahertz. A megahertz is one ... Typical radio wave frequencies are about 88~108 MHz .
Explanation:
To calculate the wavelength of a radio wave, you will be using the equation: Speed of a wave = wavelength X frequency.
Since radio waves are electromagnetic waves and travel at 2.997 X
10
8
meters/second, then you will need to know the frequency of the radio wave.
If the radio wave is on an FM station, these are in Megahertz. A megahertz is one million hertz. If the radio wave is from an AM radio station, these are in kilohertz (there are one thousand hertz in a kilohertz). Hertz are waves/second. Hertz is usually the label for the frequency of electromagnetic waves.
To conclude, to determine the wavelength of a radio wave, you take the speed and divide it by the frequency.
Typical radio wave frequencies are about
88
~
108
MHz
. The wavelength is thus typically about
3.41
×
10
9
~
2.78
×
10
9
nm
.
