i) A straight wire conductor passes vertically through a piece of cardboard sprinkled with iron fillings. Copy the diagram and shows the setting of iron fillings when a current is passed through the wire in the upward direction and the cardboard is tapped gently. Draw an arrow to represent the direction of the magnetic field lines.
ii) Name the law which helped you to find the direction of the magnetic field lines.
i)
ii) Right hand thumb Rule
i) State two ways by which the magnetic field of a solenoid can be made stronger.
ii) What material is used for making the armature of an electric bell? Give a reason for using this material.i) Name a metal that is used as an electron emitter.
ii) Give one reason for using this metal.i) Which radiation produces maximum biological damage?
ii) what happens to the atomic number of an element when the radiation named by you in part (i) above, are emitted?i) Write a relation expressing the mechanical advantage of a lever.
ii) Write an expression for the mechanical advantage of an inclined plane.
iii) Give two reasons as to why the efficiency of a single movable pulley system is always less than 100%
An erect magnified and virtual image is formed, when an object is placed between the optical centre and principal focus of a lens.
i) Name the lens.
ii) Draw a ray diagram to show the formation of the image with the above stated characteristics.Five resistors of different resistances connected together as shown in the figure. A 12 V battery is connected in the arrangement.
Calculate:
i) the total resistance in the circuit.
ii) the total current flowing in the circuit.