WorksheetsIB Physics Topic 11
Total questions: 24
Worksheet time: 17mins
Which description best applies to Lenz's Law?
An induced current occurs when a magnet passes through a tube.
When a change in magnetic field occurs to a coil the direction of current goes in the in the other direction to this change.
The direction of an induced current is such to align with the change that created it.
A magnet is a tube is always slowed by its magnetic field.
Which activity will produce the highest current?
Move the magnet bar into the coil while the coil remains stationery
Move the coil into the magnet bar while the magnet remains stationery
Move the coil and magnet towards each other
Move the coil and magnet away from each other
Transformer is device that
converts AC voltage to current
converts electrical energy to kinetic energy
converts AC voltage to a different level at the same amplitude
converts AC voltage to a different level at the same frequency
Select the facts about transformer.
Will not work with DC and AC
Will not work with DC
AC will produce change in magnetic field
AC will induce current
Primary loop is connected to the supply while secondary loop is connected to the load.
True
False
With respect to the capacitor, which relationship is true? •
C = Q×V
V = C×Q
V = Q/C
Q = C/V
Which of the following will increase the strength of an electric generator?
Use a Bigger Magnet
Move the Magnet Slower
Wrap More Coils
Use a Bigger Battery
F = BIL If the current and magnetic field are doubled, the magnetic force on the wire
halves
remains the same
doubles
quadruples
F = qvB If the speed and charge double, what happens to the magnetic force?
halves
remains the same
doubles
quadruples
Magnetic flux is measured in
teslas
coulombs
webers
farads
What does AC smoothing mean?
the process of inducing an emf (voltage) with a change in magnetic flux
Electric currents whose direction and magnitude change periodically depending on time are called alternating current
Steady current which delivers the same average power as the a.c. to a resistive load.
Making a rectified current more steady (or smooth) by placing a capacitor in parallel with the resistor
What is alternating current
the process of inducing an emf (voltage) with a change in magnetic flux
Electric currents whose direction and magnitude change periodically depending on time are called alternating current
Steady current which delivers the same average power as the a.c. to a resistive load.
Making a rectified current more steady (or smooth) by placing a capacitor in parallel with the resistor
Calculate potential difference in the secondary coil based on the information given below.
Vp = 240 V
Np = 20
Ns = 125
Vs ?
1500
500
1000
2000
Why transformers work with A.C. current but not D.C.
A.C current produces changing magnetic field.
D.C current produces changing magnetic field.
D.C current is weak
A.C current is powerful
A transformer has 100 turns in the primary coil and 25 turns in the secondary coil. When a 120 V is applied to the primary coil, what is the voltage in the secondary coil?
480V
30V
20V
450V
What is the purpose of a diode
Allow current flow in one direction and oppose current flow in the opposite direction
Allow current to flow in both directions
Create resistance within a circuit
Convert mechanical energy into electrical energy.
