GCSE-Electromagnetism Flashcards
Fleming’s left hand rule predicts the direction of the force on an electric current flowing in a …?
magnetic field
In Fleming’s left hand rule the current, field lines and force are all …?… to each other
perpendicular
In Fleming’s left hand rule the first finger represents the direction of the …?
magnetic field
In Fleming’s left hand rule the second finger represents the direction of the …?
current
In Fleming’s left hand rule the thumb represents the direction of the …?
force
Turns-ratio equation for a transformer
Vs/Vp = ns/np
Power equation for a transformer
VpIp = VsIs
The magnetic field produced by a current flowing through a coil of wire has the same shape as the field caused by a …?… …?…
bar magnet
If the current flow in a coil is clockwise as seen from one end of the coil, then that end is a …?… pole
South
If the number of turns on a current-carrying coil is increased, then the strength of its magnetic field …?
increases
If the current flowing through a coil is decreased, then the strength of its magnetic field …?
decreases
The strength of the magnetic field caused by a current-carrying coil will increase if it is given a core made of …?
iron
If a conductor and/or magnet is moved so that the conductor cuts across magnetic field lines, then …?… …?… is induced in the conductor
electric current
If the current flowing through a coil is changed, then electric current is …?… in a nearby second coil.
induced
Step-up and step-down transformers help to …?… power losses in power lines.
reduce