Answer:
Air.
Explanation:
To know which option is correct, let us consider the relationship between velocity and the wavelength of a wave. This is illustrated below:
Velocity, wavelength and frequency are related by the following equation:
Velocity = wavelength × frequency
v = λf
From the equation above, we can see clearly that the velocity is directly proportional to the wavelength.
This means that an increase in the wavelength will lead to an increase in the velocity and also, a decrease in the wavelength will lead to a decrease in the velocity.
Now, considering the table given in the question above, we can see that the wave has a higher speed in air. This simply means that the wave will also have a higher wavelength in air.
Thus, the correct answer to the question is: air
The correct option is D.
Resonance is a phenomenon in which a vibrating system or an external force induces another system to vibrate at greater amplitude at particular frequencies.
When a tuning fork is struck with another object, the tuning fork will start to vibrate as a result of the force that is exerted by the object used to struck it. This type of vibration, without direct excitation by a man is an example of resonance.
Answer:
Explanation:
Given that,
Number of turns of coil
N = 50 turns
Initial area of plane
A1 = 0.18 m²
The coil it stretch to a no area in time t = 0.1s
No area implies that the final area is 0, A2 = 0 m²
Constant magnetic field strength
B = 1.51 T
EMF?
EMF is given as
Using far away Lenz law
ε = —N• dΦ/dt
Where Φ = BA
Then,
ε = —N• d(BA)/dt
Since B is constant,
ε = —N•B dA/dt
ε = —N•B (∆A/∆t)
ε = —N•B(A2—A1)/(t2-t1)
ε = —50 × 1.51 (0—0.18)/(0.1—0)
ε =—75.5 × —0.18 / 0.1
ε = 135.9 V
The induced EMF is 135.9V
Fleming’s left hand rule stated that if the index finger points toward magnetic flux, the thumb towards the motion of the conductor, then the middle finger points towards the induced emf.
Since the area lines in the plane, then the induced emf will be out of the page
