Answer:
<em>380 kHz</em>
<em></em>
Explanation:
The speed of sound is taken as 1500 m/s
The length of the fetus is 1.6 cm long
The condition is that the wavelength used must be at most 1/4 of the size of the object that is to be imaged.
For this 1.6 cm baby, the wavelength must not exceed
λ =
of 1.6 cm =
x 1.6 cm = 0.4 cm =
0.4 cm = 0.004 m this is the wavelength of the required ultrasonic sound.
we know that
v = λf
where v is the speed of a wave
λ is the wavelength of the wave
f is the frequency of the wave
f = v/λ
substituting values, we have
f = 1500/0.004 = 375000 Hz
==> 375000/1000 = 375 kHz ≅ <em>380 kHz</em>
V o - initial velocity
v = velocity at the maximum height,
v² = v o² - 2 g h
v = 0
0 = v o² - 2 g h
v o² = 2 g h = 2 · 9.80 · 0.460
v o² = 9.052
v o = √9.052 = 3.004197 m/s ≈ 3 m/s
Answer:
A) d_o = 20.7 cm
B) h_i = 1.014 m
Explanation:
A) To solve this, we will use the lens equation formula;
1/f = 1/d_o + 1/d_i
Where;
f is focal Length = 20 cm = 0.2
d_o is object distance
d_i is image distance = 6m
1/0.2 = 1/d_o + 1/6
1/d_o = 1/0.2 - 1/6
1/d_o = 4.8333
d_o = 1/4.8333
d_o = 0.207 m
d_o = 20.7 cm
B) to solve this, we will use the magnification equation;
M = h_i/h_o = d_i/d_o
Where;
h_o = 3.5 cm = 0.035 m
d_i = 6 m
d_o = 20.7 cm = 0.207 m
Thus;
h_i = (6/0.207) × 0.035
h_i = 1.014 m
Answer:
60 N
Explanation:
This is just Newton's Second Law
F = m*a
F = ?
m = 12 kg
a = 5 m/^2
F = 5*12 = 60 Newtons
In December solstice Massachusetts receives the most indirect rays of the sun. It happened on the day of 21st of December.
<u>Explanation</u>:
Winter solstice festivities bring "stillness, light, and warmth" into this period of the occasion hustle. Keeping that in mind, we give you this gathering of mysterious occasions to stamp the day of the year (this year, Friday, December 21) with the briefest time of sunlight and the longest night of year. Also, obviously, to respect the arrival of the sun and the more extended days to come.