Answer:
The horizontal component of the velocity is the cosine of 30 degrees multiplied by 40m/s. The cosine of 30 degrees is the 0.8660 . To get the speed, multiply by 40m/s. This equals 34.64, which is approximately 35m/s.
Hope it helpss :)
The electric field is always perpendicular to the surface outside of a conductor. TRUE
<span> If an electron were placed on an electric field line, it would move in a direction perpendicular to the field. FALSE, it would move in an anti-parallel direction because its charge is negative </span>
<span>Electric field lines originate on positive charge and terminate on negative charge. TRUE ; but they can also go to infinity </span>
It is possible for two electric field lines to cross each other.
<span> Usually FALSE; though technically possible at special points where field is zero. </span>
If an electron and a positron were in the presence of a very strong electric field, they would move away from each other.
<span> TRUE; one is positive, and one is negative. If the field is strong enough, the action of the field will overcome the mutual attraction between them </span>
It is not possible for the electric field to ever be zero. FALSE: it IS possible, inside a conductor for instance
If a proton were placed on an electric field line, it would move in a direction anti-parallel to the field.
<span> FALSE: being positive, it would move in the SAME direction as the field</span>ic
Constructive interference will occur, which means the waves will combine.
In destructive inference, the waves cancel each other out.
Hope this helps :)
Answer:
<em>"the magnitude of the magnetic field at a point of distance a around a wire, carrying a constant current I, is inversely proportional to the distance a of the wire from that point"</em>
Explanation:
The magnitude of the magnetic field from a long straight wire (A approximately a finite length of wire at least for close points around the wire.) decreases with distance from the wire. It does not follow the inverse square rule as is the electric field from a point charge. We can then say that<em> "the magnitude of the magnetic field at a point of distance a around a wire, carrying a constant current I, is inversely proportional to the distance a of the wire from that point"</em>
From the Biot-Savart rule,
B = μI/2πR
where B is the magnitude of the magnetic field
I is the current through the wire
μ is the permeability of free space or vacuum
R is the distance between the point and the wire, in this case is = a
