RI Y6 Remedial EM Assignment

Raffles Institution Year 5-6 Physics Department 1 2025 Year 6 H2 Physics Remedial Chapter 16: Electromagnetism 1 (a) Fig. 1 .1 shows two identical straight wires of length L placed normal to this page with current in wire X flowing into the page and current in wire Y flowing out of the page. The two wires are positioned 0.10 m apart. Fig. 1.1 (i) Sketch and label the directions of the magnetic field lines in Fig. 1.1 assuming that both currents in wire X and Y are of the same magnitude. [2] (ii) Indicate, in Fig. 1.1, the direction of the magnetic force F on wire X and wire Y. [1] (iii) A current of 5.0 A now flows in wire X and a current of 3.0 A flows in wire Y. You may assume that at a distance, d , from a straight wire with a current, I , flowing through it, the magnetic flux density, B = 𝜇𝜇𝑜𝑜𝐼𝐼 2𝜋𝜋𝜋𝜋 . 1. Calculate the magnetic flux density at wire X due to wire Y. [1] 2. Calculate the magnetic flux density at wire Y due to wire X. [1] 3. Hence show quantitatively that the force F experienced by each wire is equal in magnitude. [3] (b) Wire Y is placed in the region between the poles of a strong magnet. Fig. 1.2 (i) Sketch in Fig. 1.2 the resultant magnetic field in the region between the poles of a magnet. [2] (ii) State the direction of the magnetic force acting on wire Y. [1] X Y

Raffles Institution Year 5-6 Physics Department 2 2 (a) A large horseshoe magnet produces a uniform magnetic field of flux density B between its poles. Outside the region of the poles, the flux density is zero. The magnet is placed on a top -pan balance and the wire XY is situated between its poles, as shown in Fig. 2. Fig. 2 The wire XY is horizontal and normal to the magnetic field. The length of wire between the poles is 4.4 cm. A direct current of magnitude 2.6 A is passed through the wire in the direction from X to Y. The reading on the top-pan balance increases by 2.3 g. (i) State and explain the polarity of the pole P of the magnet. [3] (ii) Calculate the flux density between the poles. [2] (b) A charged particle may experience a force in an electric field and in a magnetic field. State two differences between the forces experienced in these two types of fields. [2] [AJC/Prelims 2014/P2/3]

Raffles Institution Year 5-6 Physics Department 3 3 Fig. 3 below shows a current balance. The wire frame AXYC is balanced on two knife edges through which a current from a battery can be passed through. The wire frame is horizontal when there is no current. A magnetic force acts on the wire frame when a 3.0 A current flows through. (a) Explain why the current in AC causes a turning effect. [3] (b) Explain why the current in AX and CY do not contribute to the turning effect.