Recall which direction your thumb points in when you use the right-hand rule. The direction of the current.1The direction of the magnetic force.2The direction of the magnetic field.3Opposite to the current.

Which of the following can be used to determine the direction of the magnetic field around a straight current-carrying wire?The right-hand grip ruleFleming’s right-hand ruleThe left-hand grip ruleFleming’s left-hand rule2In Fleming’s left-hand rule, what does the first (index) finger represent?The (conventional) current directionThe electric field directionThe direction of the force which is exerted on the conductorThe magnetic field direction3An electromagnet can be produced by passing an electric current through a solenoid.  Which of the following will NOT increase the strength of the magnetic field around such a solenoid?Increasing the current through the solenoidPlacing a soft iron core into the middle of the solenoidMoving the turns of wire that make up the solenoid further apartUsing more turns of wire in the solenoid4Which of the following will NOT increase the size of the force which is exerted on a current-carrying conductor in a magnetic field?Increasing the magnetic flux density of the magnetic fieldIncreasing the current which is flowing through the conductorIncreasing the amount of time which the conductor spends in the magnetic fieldIncreasing the length of the conductor which is in the magnetic field5What is the unit for the magnetic flux density of a magnetic field?TeslaBarNewtons per ampMagnetons6Which of the following will NOT increase the speed at which a d.c. (direct current) electric motor rotates?Swapping around the electrical connections to the battery which powers the motorReplacing the wire which forms the coil with a type of wire which has a lower electrical resistanceLubricating the moving parts of the motorIncreasing the strength of the magnet inside the motor7A 2 cm-long piece of wire is placed at right angles to a magnetic field which has a magnetic flux density of 10 mT.  Calculate the force which will be exerted on the wire when a current of 1 A flows through it.20 N2 × 10-4 N0.02 N0.2 N

Recall which direction your thumb points in when you use the right-hand rule.

Choose the incorrect statement(1) Fleming's right-hand rule is a simple ruleto know the direction of induced current(2) The right-hand thumb rule is used to findthe direction of magnetic fields due tocurrent carrying conductors(3) The difference between the direct andalternating currents is that the direct currentalways flows in one direction, whereas thealternating current reverses its directionperiodically(4) In India the AC changes direction afterevery (1/50) second.

Describe how to use the right-hand rule to find the magnetic field of a current-carrying wire.

A wire carries a current downward and is placed in a magnetic field that points directly out of the page. What is the direction of the magnetic force on the wire?a.To the rightb.To the leftc.Downwardd.Upward