Answer:1). Distance of far point x=0.9m
Therefore, since the image is virtual
-f=-x = -0.9m
Power of the concave lenses = 1/f = 1/-0.9
= -1.11D
2 ) near point is 21cm = 0.21m
Power = 4-1/near point
= 4/0.21
= 14.2D.
Answer:
The induced voltage is
Explanation:
From the question we are told that
The number of turns is
The diameter is
The initial magnetic field is
The final magnetic field is
The time taken is
The radius is mathematically evaluated as
substituting values
Generally the induced emf is mathematically represented as
Where is the change in magnetic flux of the wire which is mathematically represented as
=>
Here
since the axis of the coil is parallel to the field
Where A is the cross-sectional area of the coil which is mathematically represented as
So the induced emf
Here we substituted the values of
Sound waves in the air make tiny vibrations