So we want to know what kind of magnets do we have in the electric motor. So the central rotor is usually the electromagnet and the field magnet is usually the permanent magnet. This is characteristic for most small electric motors. So the correct answer would be D) permanent magnets, electromagnet.
Answer:
For and , the expression is satisfied dimensionally.
Explanation:
is a position and has a dimension of length, .
is acceleration which has dimensions of .
is time with dimension of .
Since is dimensionless, we do not factor it into the dimensional equation as below:
Expanding the first term on the right hand side,
Applying the laws of indices,
The index of each fundamental dimension must be equal on both sides.
For ,
For ,
But
Thus, the equation is dimensionally satisfied for the given values of and .
Answer:
Explanation:
Given
mass of disk
radius of disc
mass of ring
Force
Total moment of inertia
=Moment of inertia of Disc +Moment of Inertia of ring
Now Torque is
Now using
here
<span>
Elecromagnetic waves can travel through a vacuum, but a mechanical wave cannot.
Mechanical waves can only exist in a medium, such as air or water. Electromagnetic
waves behave like waves and particles, but mechanical waves only behave
like waves. </span>