Revision: Electromagnetism Report a question What's wrong with this question? You cannot submit an empty report. Please add some details. 19 Electromagnetism - Revision Quiz Test your understanding of Electromagnetism here: 1 / 5 1) A student sets up the circuit as shown below to magnetise a steel bar. Which of the following statements about the circuit set up is not correct? The same circuit can demagnetise a magnet if an a.c. source is used. The longer the circuit is on, the stronger the magnetisation of the steel bar. A north-pole will be set up at Q when the circuit is on. The steel bar and the solenoid should be placed along a North-South direction. 2 / 5 2) A horseshoe magnet rests on a mass balance with a horizontal metal rod XY situated between the poles of the magnet. The rod is connected to a circuit as shown. With no current in the rod, the reading on the balance is 142.0 g. With a current of 2.0 A in the rod in the direction Y to X, the reading on the balance changes to 144.6 g. The battery polarity is reversed and the variable resistor is adjusted so that there is a current of 3.0 A in the rod in the direction X to Y. What is the new reading on the balance? 138.1 g 148.5 g 145.9 140.7 g 3 / 5 3) 2011 S4 EOY P1 Q25 The diagram below shows a simple electric motor which has a rectangular coil that is linked to a power supply. The rectangular coil rotates when it is mounted between two magnetic poles N and S. Which statement is true? The coil moves downwards when a direct current flows through the coil from X to Y. The coil rotates clockwise and comes to rest in a vertical position when a direct current flows through the coil from X to Y. The coil rotates anticlockwise when a direct current flows through the coil from X to Y. The coil rotates continuously clockwise when an alternating current flows through the coil. 4 / 5 4) The diagram shows the structure of an electric bell. Which parts of the bell are made of soft iron? cores, armature and yoke connecting wires, cores and armature spring, armature and yoke cores, armature and bell 5 / 5 5) 2018 S4 EOY P1 Q27 The diagram below shows the cross-section of 4 wires. The wires are long and run parallel to each other. Two of the wires have current going into the page and two have current coming out of the page. The magnitude of the currents in all four wires is the same. What is the direction of the magnetic field at P? (Ignore the Earth's magnetic field.) To the left Downwards To the right Upwards Your score is Restart quiz
