Answer:
A) 1568.60 Hz
B) 1437.15 Hz
Explanation:
This change is frequency happens due to doppler effect
The Doppler effect is the change in frequency of a wave in relation to an observer who is moving relative to the wave source

where
C = the propagation speed of waves in the medium;
Vr= is the speed of the receiver relative to the medium,(added to C, if the receiver is moving towards the source, subtracted if the receiver is moving away from the source;
Vs= the speed of the source relative to the medium, added to C, if the source is moving away from the receiver, subtracted if the source is moving towards the receiver.
A) Here the Source is moving towards the receiver(C-Vs)
and the receiver is standing still (Vr=0) therefore the observed frequency should get higher

B)Here the Source is moving away the receiver(C+Vs)
and the receiver is still not moving (Vr=0) therefore the observed frequency should be lesser

momentum= mass × velocity
p= 50×18
momentum= 900 kg m/s
No thats false. If your trying to say is true that people BELIEVED that then yes its true people believed it but if your talking about that question then its false
Answer:
the magnitude and direction of d → B on the x ‑axis at x = 2.50 m is -6.4 × 10⁻¹¹T(Along z direction)
the magnitude and direction of d → B on the z ‑axis at z = 5.00 m is 1.6 × 10⁻¹¹T(Along x direction)
Explanation:
Use Biot, Savart, the magnetic field

Given that,
i = 1.00A
d → l = 4.00 m m ^ j
r = 2.5m
Displacement vector is


=2.5m
on the axis of x at x = 2.5

r = 2.5m
And unit vector


Therefore, the magnetic field is as follow


(Along z direction)
B)r = 5.00m
Displacement vector is


=5.00m
on the axis of x at x = 5.0

r = 5.00m
And unit vector


Therefore, the magnetic field is as follow


(Along x direction)
The height of the oil column above the water in the vessel is determined as 2 cm.
<h3>
Pressure of the vessel</h3>
The pressure of the vessel due to water, oil and silver poured into the vessel is determined from mercury column.
let level of mercury = 20 cm + 0.5 cm = 20.5 cm
20.5 cmHg = 205 mmHg
1 mmHg = 133.32 Pa
205 mmHg = 27,330.6 Pa
<h3>Height of the liquids in the vessel</h3>
P = ρgh
where;
ρ is the density of water, oil and silver respectively
ρ = 1000 kg/m³ + 881 kg/m³ + 10,800 kg/m³ = 12,681 kg/m³
h = P/(ρg)
h = (27,330.6) / (12,681 x 9.8)
h = 0.22 m
h = 22 cm
<h3>Height of oil column</h3>
Oil is less dense than water and will float on water.
Height of oil column = 22 cm - 20 cm = 2 cm
Learn more about density here: brainly.com/question/6838128
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