Answer:
d) 1.2 mT
Explanation:
Here we want to find the magnitude of the magnetic field at a distance of 2.5 mm from the axis of the coaxial cable.
First of all, we observe that:
- The internal cylindrical conductor of radius 2 mm can be treated as a conductive wire placed at the axis of the cable, since here we are analyzing the field outside the radius of the conductor. The current flowing in this conductor is
I = 15 A
- The external conductor, of radius between 3 mm and 3.5 mm, does not contribute to the field at r = 2.5 mm, since 2.5 mm is situated before the inner shell of the conductor (at 3 mm).
Therefore, the net magnetic field is just given by the internal conductor. The magnetic field produced by a wire is given by

where
is the vacuum permeability
I = 15 A is the current in the conductor
r = 2.5 mm = 0.0025 m is the distance from the axis at which we want to calculate the field
Substituting, we find:

Answer:
Instantaneous speed means speed at any instant
that means Speed is changing with time
You know speed is distance/time
So that means distance is also changing with time
So we take infinitesimal small distance per infinitesimal small time As we assume speed is constant in infinitesimal small time dt
So, we take speed = ds/dt
ds = infinitesimal small distance
dt = infinitesimal small time
As its ratio is equal to speed at any instant
Note : We are taking infinitesimal small distance
But :) we are taking infinitesimal small time also
As you know if denominator is small fraction is large So fraction always give large value
So it's not O ( this makes confuse to most of students)
So, thanks
Good question
Keep thinking like this :)
The answer is
Pitch of the buzzer increased (higher tone) as it moves towards the observer
A compound is the substances that are formed by combining two are more chemical elements. A mixture is a substance created from two or more matter that can be separate with the help of physical methods. ... Mainly pure water is part of the compound. Mixtures fall under impure water.
Hope this helps!
Have a great day!