Explanation:
It is given that,
Frequency of diagnostic ultrasound, f = 3.82 MHz = 3820 Hz
The speed of the sound in air, v = 343 m/s
(a) We need to find the wavelength in air of such a sound wave. Let it is given by λ₁
i.e. 
(b) If the speed of sound in tissue is 1650 m/s .
Hence, this is the required solution.
Answer is C because I’m exothermic energy products are always lower than reactants
For this case we have that by definition, the average power is given by:
Where:
W: It is the work done
t: It's time
According to the data we have to:
So:
Answer:
By Newton's second law, the net force on the object is
∑ <em>F</em> = <em>T</em> - <em>mg</em> = - <em>ma</em>
where
• <em>T</em> = 25 N, the tension in the string
• <em>m</em> is the mass of the object
• <em>g</em> = 9.8 m/s², the acceleration due to gravity
• <em>a</em> = 2.0 m/s², the acceleration of the elevator-object system
Solve for <em>m</em> :
25 N - <em>m</em> (9.8 m/s²) = - <em>m</em> (2.0 m/s²)
==> <em>m</em> = (25 N) / (9.8 m/s² - 2.0 m/s²) ≈ 3.2 kg
Answer:
Option A
Measures light from distant objects
Explanation:
A spectroscope is used to measure the use of light from a distant object to work out the object is made of.
It could be the single-most powerful tool astronomers use.
Professor Fred Watson from the Australian Astronomical Observatory says that "It lets you see the chemicals being absorbed or emitted by the light source"
