Are you totally charged and able to go on your Yearly exams? Effectively, on this submit, we’ve given you ten difficult electrical energy and magnetism follow inquiries to see how properly you’ve attracted all of that 12 months 11 physics information.
Electrical energy and Magnetism Observe Questions
Query 1
A steel rod with a unfavorable cost is positioned close to a impartial steel conductor:
a) Outline the time period ‘polarisation’ with respect to electrical cost.
b) Present the cost distribution within the impartial sphere.
c) Define a process whereby the sphere beneficial properties a unfavorable cost.
d) Define a process whereby the sphere beneficial properties a constructive cost.
Query 2
Draw the electrical or magnetic area traces within the following diagrams:
Query 3
Calculate the power on a take a look at cost of (+0.5text{ }mutext{C}) within the following instances:
a) (0.3text{ m}) away from a (+2.2text{ }mutext{C}) cost.
b) Inside an electrical area of energy ( 15text{ Vm}^{-1}) upwards.
c) Within the diagram beneath:
Query 4
A scientist is inspecting the movement of particular person electrons in a particle accelerator. The electrons in query have a velocity of ( 900,000text{ ms}^{-1}).
a) Calculate the work on every electron required to realize this pace, if the electrons started at relaxation.
b) Decide the voltage required to speed up the electrons to this pace.
c) ( 2.5 occasions 10^{20}) electrons go by a single level each second. Calculate the magnitude of the present.
d) Calculate the minimal energy required to realize the present in (c).
Query 5
A voltage is utilized throughout two parallel plates as within the diagram beneath:
a) Draw the electrical area between the plates and point out the energy of the electrical area.
b) A cost of (-100text{ }mutext{C}) is suspended immobile between the plates. Calculate its mass.
c) Calculate the work accomplished by the electrical area on the (-100text{ }mutext{C}) cost if it strikes down by (1text{ cm}).
Query 6
An electrical area has been arrange between two parallel plates as proven beneath:
a) What’s the distance between the parallel plates?
b) Draw on the diagram an equipotential line akin to (4text{ V}) above the unfavorable plate.
c) A unfavorable cost is moved upwards alongside the (4text{ V}) equipotential line from (b). Define the quantity of labor accomplished by the electrical area because the cost strikes from one aspect of the equipotential line to the opposite and justify your reply.
Query 7
A scholar was investigating Ohm’s legislation by measuring the voltage drop throughout a resistor as a operate of present. Their recorded outcomes are beneath:
| Present (Amps) | Voltage (Volts) |
| 0.2 | 2.13 |
| 0.4 | 4.29 |
| 0.5 | 5.20 |
| 0.6 | 6.33 |
| 0.7 | 7.38 |
a) By plotting the outcomes on the graph beneath, decide if the resistor is ohmic.
b) Decide the resistance of the resistor for a present of (0.3 textual content{ A}).
Query 8
A scholar constructs a circuit with an ammeter as proven beneath:
a) Decide the overall resistance of the circuit.
b) If the studying on the ammeter is (1.5text{ A}), calculate the voltage offered by the battery.
c) Decide the voltage drop throughout every of the resistors.
Query 9
Take into account the circuit beneath:
a) Decide the overall present within the circuit.
b) Decide the voltage drop throughout every resistor.
c) Calculate the ability dissipated by every resistor.
d) Clarify what would occur if a wire was related between factors A and B on the circuit [Hint: calculate the potential at points A and B].
Query 10
A solenoid is {an electrical} machine that can be utilized to generate a magnetic area, consisting of coils of wire wrapped round a core:
The solenoid within the above diagram has (10) turns, and is (20 textual content{ cm}) lengthy.
a) Draw the magnetic area that will likely be generated by the solenoid. Label the north and south poles which are fashioned.
b) Calculate the energy of the magnetic area generated by a present of (3.5 textual content{ A}) operating by way of the solenoid. Assume that there is no such thing as a materials within the core.
c) Define how the magnetic area would change if a ferromagnetic materials was added to the core.
Options
Query 1:
a) Polarisation refers to a separation of cost whereby one finish of an object has a internet constructive cost and the opposite finish has a internet unfavorable cost.
b)
c) Charging by contact: if the negatively charged rod touches the sphere some unfavorable cost will likely be transferred onto the sphere, giving the sphere a internet unfavorable cost.
d) Charging by induction: The negatively charged rod is held near the sphere however doesn’t make contact. The sphere is as an alternative related to the bottom with a conductor. Electrons transfer from the sphere to the bottom, leaving the sphere with a internet constructive cost.
Query 2:
a)
b)
c)
d)
Query 3:
a) (0.11 textual content{ N}) repulsive
b) (7.5 occasions 10^{-6} textual content{ N}) upwards
c) (1.48 occasions 10^{-4} textual content{ N}) to the appropriate
Query 4:
a) (3.69 occasions 10^{-19} textual content{ J})
b) (2.3 textual content{ V})
c) (40 textual content{ A})
d) (92 textual content{ W})
Query 5:
a)
b) (3.06 occasions 10^{-3}textual content{ kg})
c) (-3 occasions 10^{-4}textual content{ J})
Query 6:
a) (0.02 textual content{ m})
b)
c) Zero work is required to maneuver alongside an equipotential. Equipotential surfaces are perpendicular to the sphere, and therefore to the electrical power a cost would expertise. Thus the angle between the displacement and the power from the electrical area is (90^circ) and the work accomplished by the electrical area is (W = F s textual content{ cos }theta = F s textual content{ cos }90^circ = 0).
Query 7:
a)
The resistor is ohmic as voltage and present are proportional, indicated by the graph being a straight line.
b) (10.5 textual content{ }Omega), resistance needs to be obtained from the gradient of the road of finest match (and is fixed, unbiased of present).
Query 8:
a) (8.54 textual content{ }Omega)
b) (12.8 textual content{ V})
c) (2.3 textual content{ V}) for the (4.2 textual content{ }Omega) resistor.
(2.3 textual content{ V}) for the (2.5 textual content{ }Omega) resistor.
(10.5 textual content{ V}) for the (7 textual content{ }Omega) resistor.
Query 9:
a) (9 textual content{ A})
b) (18 textual content{ V}) for the (3 textual content{ }Omega) resistor.
(12 textual content{ V}) for the (2 textual content{ }Omega) resistor.
(18 textual content{ V}) for the (6 textual content{ }Omega) resistor.
(12 textual content{ V}) for the (4 textual content{ }Omega) resistor.
c) (108 textual content{ W}) for the (3 textual content{ }Omega) resistor.
(72 textual content{ W}) for the (2 textual content{ }Omega) resistor.
(54 textual content{ W}) for the (6 textual content{ }Omega) resistor.
(36 textual content{ W}) for the (4 textual content{ }Omega) resistor.
d) Nothing would occur. The potential at level A is (12 textual content{ V}) and the potential at level B is (12 textual content{ V}). Since there is no such thing as a potential distinction between factors A and B, no present will circulate if they’re related.
Query 10:
a)
b) (B = 2.2 occasions 10^{-4}textual content{ T})
c) The magnetic area energy would enormously enhance.
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