Physics - Electricity (6) Flashcards
What effect does increasing distance have on the velocity in parallel plates?
This decreases the electric field strength. These two factors cancel out, and the velocity is unchanged.
Adding resistance in a series
Resistance increases. The bulbs share a pathway, and each added bulb increases resistance
Adding resistance in parallel
Decreases total resistance (another pathway)
2 in series 1 in parallel. Why isn’t this good?
- If 1 is broken, the series won’t work.
- The lamps won’t recieve the voltage they’re rated for.
- The lamps will shine different brightnesses
Why do electrons produce a force when in a magnetic field?
The electron’s field combines with the existing field, resulting in a stronger force on one side. It experiences a net force from the strong field to the weak field.
Adding resistance to one bulb in parallel
Decreases resistance, increases current, V=IR, so the voltage used by the other increases. This in turn must decrease the other’s voltage.
Describe the diagram of electric fields
The lines are parallel and equally spaced. This shows that the elecric field is uniform between plates.
In a magnetic field, when is voltage produced?
Maximum voltage is induced when the coil velocity is 90 degrees to the field.
No voltage is where the coil velocity is with the field
In magnetic fields, how does the electrostatic force change while moving in the field.
It doesn’t. The E doesn’t change between the parallel plate and the charge is constant. F won’t change.
Why can’t magnetic fields be used for circuits?
The wire doesn’t form a circuit, so no current will flow through the bulb and it won’t glow.
How are voltages induced in magnetic fields?
When wires cuts across magnetic field lines, it induces a voltage. The direction is the right-hand rule. There is a separation of charges.
What does an ammeter being placed parallel to a bulb do?
It acts like a short circuit, the bulb won’t glow. Resistance has decreased, so current increases. The brightness of the other bulbs increase.
Why can’t a full circuit be in a magnetic field?
The current would be zero. The currents of each side will be in opposite directions and cancel each other out.
In magnetic fields, what happens when we give it a push?
There is an induced voltage as it has a current. The force opposes the motion, so it slows down.
