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.
It is called "distance". In fact, distance measures how far apart two points are from each other, and it is always a positive number.
In mathematics, for instance, the distance between two points of coordinates (x1,y1) and (x2,y2) on a xy-plane is defined as

and by definition, this number is always positive.
Answer:
(c) increase by a factor of four
Explanation:
the formular for the relationship between energy and current is E= I²Rt (Heat energy)
the heater is fairly independent of its temperature , and given the time to be constant.
with the current being doubled,
E = I² Rt
E/ I² = K
=
E2 = 
I2 = 2* I1
E2 = E1 * 4*I1² / I1²
dividing , we have that E2 = 4 * E1
which means during the same time interval the amount of energy will increase by a factor of four.
Answer:
1.7 × 10^11 Pa
Explanation:
Please see the attachments below
The question is not well presented.
There is ______ shift in sound frequency for observers towards whom the source is approaching.
Answer:
The gap should be filled with an apparent upward
Explanation:
The Doppler effect (also referred to as the Doppler shift) is the difference in frequency of a wave when related to an observer who has a relative movement to the wave source
The Doppler effect can be observed to occur with all types of waves - most notably water waves, sound waves, and light waves
The Doppler effect describes sound as an effect which is produced from a moving source of wave.
According to the Doppler effect;
When the source of waves in which there is an apparent upward shift in frequency for observers towards whom the source is approaching.