The answer is B. resistance
Answer:
the magnetic field experienced by the electron is 0.0511 T
Explanation:
Given the data in the question;
Wavelength λ = 21 cm = 0.21 m
we know that Bohr magneton μ
is 9.27 × 10⁻²⁴ J/T
Plank's constant h is 6.626 × 10⁻³⁴ J.s
speed of light c = 3 × 10⁸ m/s
protein spin causes magnetic field in hydrogen atom.
so
Initial potential energy = -μ
B × cos0°
= -μ
B × 1
= -μ
B
Final potential energy = -μ
B × cos180°
= -μ
B × -1
= μ
B
so change in energy will be;
ΔE = μ
B - ( -μ
B )
ΔE = 2μ
B
now, difference in energy levels will be;
ΔE = hc/λ
2μ
B = hc/λ
2μ
Bλ = hc
B = hc / 2μ
λ
so we substitute
B = [(6.626 × 10⁻³⁴) × (3 × 10⁸)] / [2(9.27 × 10⁻²⁴) × 0.21 ]
B = [ 1.9878 × 10⁻²⁵ ] / [ 3.8934 × 10⁻²⁴ ]
B = 510556326.09
B = 0.0511 T
Therefore, the magnetic field experienced by the electron is 0.0511 T
1/f= 1/di+1/do
1/f=1/90m+1/40m
1/f ≈27.7m
Answer:

Explanation:

Cross multiply


cross multiply

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Answer:
The angular acceleration is zero
Explanation:
When an object is in rotational motion, it has a certain angular velocity, which is the rate of displacement of its angular position.
This angular velocity can change or remain constant - this is given by the angular acceleration, which is:

where
is the change in angular velocity
is the time elapsed
Therefore, the angular acceleration is the rate of change of angular velocity.
In this problem, the bicycle rotates at a constant angular velocity of

This means that the change in angular velocity is zero:

And so, that the angular acceleration is zero:
