LEGIT WASSCE /NOVDEC📄🗒️📃📝

Q3xi. Precautions taken to ensure accurate results i) Clean the ends of the connecting wires by sand paper. (ii) The connections should be tight. (iii) Close the key (K) only when readings are to be taken. (iv) Zero errors and the ranges of the ammeter and voltmeter should be noted.

Precautions taken to ensure accurate results i) Clean the ends of the connecting wires by sand paper. (ii) The connections should be tight. (iii) Close the key (K) only when readings are to be taken. (iv) Zero errors and the ranges of the ammeter and voltmeter should be noted.

2b.i critical angle, in optics, the greatest angle at which a ray of light, travelling in one transparent medium, can strike the boundary between that medium and a second of lower refractive index without being totally reflected within the first medium

The centre of gravity(C.G.) of a body is defined as the point about which the algebraic sum of moments of weights of all the particles constituting the body is zero. The entire weight of the body can be considered to act at this point, howsoever the body is placed.

Biology practical

The options are important than the compulsory one

Solution to 8a i. Contact forces are forces which are in contact or in touch with the body to which they are applied WHILE Force field are forces whose sources do not require contact with the body to which they are applied. Examples of contact forces are push,pull, tension, reaction and frictional forces WHILE Examples of force fields are gravitational force, electric force, magnetic force ii. Gravitational field intensity at any point in a gravitational field is defined as the force per unit mass on a body at that pot.

Objectives

Solution to Q7 7a. doping is the intentional introduction of impurities into an intrinsic semiconductor for the purpose of modulating its electrical, optical and structural properties. 7b. Adding small amounts of impurities allows control of the conductivity of the semiconductor: shallow donors, such as phosphorous in silicon, produce n-type conductivity (carried by electrons), and shallow acceptors, such as boron in silicon, produce p-type conductivity (carried by holes)

Solution to Q5 *Magnets are used in magnetic compass, doorbells, refrigerators. *Magnets are used in dynamos, motors, loudspeakers, microphones etc. * Ceramic magnets are used in computers. *Magnets are used in toys to give a magic effect.

Solutions to Q6 Q6. •The three characteristics of laser are •Superior Monochromatism •Laser lights are single wavelength light. Superior Directivity •Laser beam is emitted in a specific direction. Superior Coherence •Laser lights have the same phase difference.

Solution to Q7 7a. doping is the intentional introduction of impurities into an intrinsic semiconductor for the purpose of modulating its electrical, optical and structural properties. 7b. Adding small amounts of impurities allows control of the conductivity of the semiconductor: shallow donors, such as phosphorous in silicon, produce n-type conductivity (carried by electrons), and shallow acceptors, such as boron in silicon, produce p-type conductivity (carried by holes)