Answer:
The length is 
Explanation:
From the question we are told that
The frequencies of the two successive harmonics are
, 
The speed of sound in the air is 
Generally the frequency of a given harmonic is mathematically represented as

Here n defines the position of the harmonics
Now since the position of both harmonic is not know but we know that they successive then we can represented them mathematically as

and

So

=> 
=> 
It should be C. If the object is denser than the fluid, it will sink. If it isn't, it will float
Given Information:
Length of wire = 132 cm = 1.32 m
Magnetic field = B = 1 T
Current = 2.2 A
Required Information:
(a) Torque = τ = ?
(b) Number of turns = N = ?
Answer:
(a) Torque = 0.305 N.m
(b) Number of turns = 1
Explanation:
(a) The current carrying circular loop of wire will experience a torque given by
τ = NIABsin(θ) eq. 1
Where N is the number of turns, I is the current in circular loop, A is the area of circular loop, B is the magnetic field and θ is angle between B and circular loop.
We know that area of circular loop is given by
A = πr²
where radius can be written as
r = L/2πN
So the area becomes
A = π(L/2πN)²
A = πL²/4π²N²
A = L²/4πN²
Substitute A into eq. 1
τ = NI(L²/4πN²)Bsin(θ)
τ = IL²Bsin(θ)/4πN
The maximum toque occurs when θ is 90°
τ = IL²Bsin(90)/4πN
τ = IL²B/4πN
torque will be maximum for N = 1
τ = (2.2*1.32²*1)/4π*1
τ = 0.305 N.m
(b) The required number of turns for maximum torque is
N = IL²B/4πτ
N = 2.2*1.32²*1)/4π*0.305
N = 1 turn
E, 63% of the value. I forget the rationale behind it but I learnt that in engineering. 90% confident for that answer.
Answer:
C: You must know force and distance to calculate both.
Explanation:
A force is said to have done work, when it has succeeded in causing displacement in an object from its starting point.
Power can be defined as the rate of doing work.
The work can be calculated using the following formula:
Work done = Force × Displacement
The power can be calculated using the following formula:
Power = Work \ Time
In order to calculate the work and power, the force and distance should be known. The force and distance will help in the calculating the work, which will in turn help in the calculation of the power of the object.
Hence, the answer is you must know force and distance to calculate both.