SS 1 Third Term Examination Physics
THIRD TERM
Examination malpractices may lead to a repeat of the subject or suspensions don’t be involved.
SUBJECT PHYSICS
CLASS: S. S. S ONE
DURATION 1HR 30MINS
SECTION B
INSTRUCTION: Attempt any three questions from this section.
- (a) A battery of four cells each of e.m.f. 1.5V and internal resistance 1.0 Ω is connected in series with a parallel combination of two 2 Ω resistors. Draw the circuit diagram and calculate: (i) the combined external resistance (ii) the current in the circuit (iii) the lost volts in the battery (iv) the current in one of the two resistors 8marks
(b) State Ohms law 2marks
- (a) Determine the length and conductivity of a wire with diameter 2.0mm constructed from an alloy of resistivity 22×10-8Ωm, if its resistance is 0.42Ω
(π=22/7) 4marks
(b) Electricity is supplied to Elias international school along a cable of total resistance 0.5Ω with the maximum current drawn from the main as 100A. The maximum energy dissipated as heat for 1hour is? 3marks
(c) Mention 3 factors that affect the resistance of a wire 3marks
- (a) A landlord has six 30w electric lighting bulb, four 60w bulb and two 200w bulb. If he has all the point on for 10hrs, what is the bill for the month of February 2018? 8marks
(b) State four factors that affect the rate of diffusion 2marks
- (a) A battery of 20v and internal resistance 5Ω is connected to a resistor 0f 20Ω. Calculate the value of: (i) electric current (ii) terminal voltage (iii)lost voltage 6marks
(b) Give two differences between crystalline and amorphous substances 2marks
(c) Give two ways of reducing surface tension 2marks
- (a) Sketch the graph of the relation between the extension of a spiral spring and the load attached to it when it is gradually loaded up to elastic limit. Indicate the following points: elastic limit, yield point, maximum load, and breaking point. 5marks
(b) If the spring has a stiffness of 950Nm-1, what work will be done in extending the spring by 60mm? 3marks
(c) Define surface tension 2marks