Answer:
Explanation:
It is given that,
Number of turns in the coil, N = 220
Diameter of the coil, d = 4.4 cm
Radius of the coil, r = 2.2 cm = 0.022 m
Magnetic field produced by the poles of magnet, 
Current flowing in the coil, I = 15 A
Let M is the coil's magnetic dipole moment. Its formula is given by :



So, the coil's magnetic dipole moment is
. Hence, this is the required solution.
Answer:
8 signals received by twin A during the trip.
Explanation:
Given that,
Distance = 12 light year
Speed = 0.6 c
Time = 1 year
We need to calculate the time by A
Using formula of time

Put the value into the formula


Similarly,
The expression for distance cover by A



We need to calculate the time
Using formula of time



We need to calculate the signals received by twin A
Using formula for number of signals

Put the value into the formula


Hence, 8 signals received by twin A during the trip.
Answer:
76.74 Hz
Explanation:
Given:
Wave velocity ( v ) = 330 m / sec
wavelength ( λ ) = 4.3 m
We have to calculate Frequency ( f ):
We know:
v = λ / t [ f = 1 / t ]
v = λ f
= > f = v / λ
Putting values here we get:
= > f = 330 / 4.3 Hz
= > f = 3300 / 43 Hz
= > f = 76.74 Hz
Hence, frequency of sound is 76.74 Hz.
Answer:
38 m
Explanation:
Number of turns=N=100
Magnetic field=B=0.50 T
Frequency of the generator=f=60 Hz
Rms value of emf=
We have to find the length of the wire from which the coil is made.
Peak value of emf=
Length of wire=
Substitute the values
Length of wire=
Length of wire=38 m
Hence, the length of wire from which the coil is made=38 m