Answer:
Lenz’s law states that an induced magnetic field in a conductor opposes the applied flux through the conductor.
Explanation:
According to the Lenz's law, the direction of induced e.m.f is such that it generates a current which in turn produces a magnetic field that would oppose the change causing it.
In other words, the direction of any magnetic induction effect is such that it opposes the cause of the effect.
Therefore; an induced magnetic field in a conductor, opposes the applied flux through the conductor.
She does work from the moment she touches the book until she lets it go. Work is anything that requires energy. Therefore, she is working as she picks up the book, carries it, and when she is lifting it onto the shelf.
Answer:
Modulation
Explanation:
Modulation is the the process whereby a waveform has one or more of it's properties varied. Amplitude, frequency and phase are all properties of a waveform which can be varied hence Modulation is the process of sending data over a signal by varying either its amplitude, frequency or phase.
Because of the parameters that we are given in the question, the right current formula that should be used for this physics problem is:
I = P/V
Where:
I = Current
P = Power and
V = Voltage
From the question, we are told that:
P = 16 W
V = 9 V
Thus, current = P/V = 16/9 = 1.78
Therefore, The current used by the camcorder is 1.8 Amphere.
Answer:
y = 2.74 m
Explanation:
The linear thermal expansion processes are described by the expression
ΔL = α L ΔT
Where α the thermal dilation constant for concrete is 12 10⁻⁶ºC⁻¹, ΔL is the length variation and ΔT the temperature variation in this case 20ªc
If the bridge is 250 m long and is covered by two sections each of them must be L = 125 m, let's calculate the variation in length
ΔL = 12 10⁻⁶ 125 20
ΔL = 3.0 10⁻² m
Let's use trigonometry to find the height
The hypotenuse Lf = 125 + 0.03 = 125.03 m
Adjacent leg L₀ = 125 m
cos θ = L₀ / Lf
θ = cos⁻¹ (L₀ / Lf)
θ = cos⁻¹ (125 / 125.03)
θ = 1,255º
We calculate the height
tan 1,255 = y / x
y = x tan 1,255
y = 125 tan 1,255
y = 2.74 m