Answer:
f = 7.97 x 10⁶ Hz = 7.97 MHz
Explanation:
The speed of a wave is given by the following formula:

where,
v = speed of the ultrasound wave through human tissue = 1540 m/s
f = frequency of ultrasound wave required = ?
λ = wavelength of ultrasound waves = smallest detail required = 0.193 mm
λ = 0.193 mm = 1.93 x 10⁻⁴ m
Therefore,
<u>f = 7.97 x 10⁶ Hz = 7.97 MHz</u>
Answer:
a,b) #_ {electron} = 1.64 10¹⁹ electrons, c) R = 19.54 Ω, d) V = 10.3 V
Explanation:
a and b) The current is defined as the number of electrons that pass per unit of time
let's look for the load
Q = I t
Q = 0.526 5
Q = 2.63 C
Let's use a direct rule of three proportions. If an electron has a charge of 1.6 10⁻¹⁹ C, how many electrons does 2.63 C have?
#_ {electron} = 2.63 C (1 electron / 1.6 10⁻¹⁹)
#_ {electron} = 1.64 10¹⁹ electrons
c) the resistance of a wire is given by
R = ρ l / A
where the resistivity of tungsten is 5.6 10⁻⁸ Ω
the area of the wire is
A = π r2 = π d²/4
we substitute
R = 
let's calculate
R = 5.6 10⁻⁸ 0.580
R = 19.54 Ω
d) let's use ohm's law
V = i R
V = 0.526 19.54
V = 10.3 V
The change in velocity is 10 mi/h (4.47 m/s)
Explanation:
The change in velocity of the motorcyclist is given by

where
v is the final velocity
u is the initial velocity
In this problem, we have
u = 0 (the motorbike starts from rest)
v = 10 mi/h
Therefore, the change in velocity is

And keeping in mind that
1 mile = 1609 m
1 h = 3600 s
We can convert it into m/s:

Learn more about velocity:
brainly.com/question/5248528
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Car is moving on the glassy slope with constant speed
Now we know that

so acceleration is rate of change in velocity
as we know that velocity is constant here so acceleration is zero
so here

now as we know by Newton's II law

since a = 0

so net force will be ZERO on it during this motion