Traditionally, the basis of overhead absorption was the number of labour hours expected within the budget period and this was then used to calculate an absorption rate per labour hour. This was then used to attribute costs to the cost units on the basis of the number of labour hours used to produce the cost unit. Alternative bases of apportioning exist such as the number of machine hours or the percentage of particular elements of prime costs incurred in respect of cost units. If the method of manufacture is machine intensive for example, it is more realistic to absorb the overhead cost on the basis of the number of machine hours instead of the number of labour hours. A further development is to divide the overheads into those costs, which are labour related, and those, which are machine hour, related and apply a separate absorption rate to each part of the overhead cost. This is the use of multiple rates similar to the principle of activity bases costing (ABC). ABC is based on the principle that activities cause costs and therefore the use of activities should be the basis of attributing costs to cost units. Costs are identified with particular activities and the performance of those activities is linked with products.

1.      Which material is suitable for making standard resistors?

2.      State the unit of temperature coefficient of resistance (α)?

3.      What happens to the resistivity and conductivity of a metal when its temperature is increased

4.      Nichrome has weak temperature dependence values with resistivity, explain

5.      How does temperature affect the resistivity of semiconductors and insulators

6.      The resistivity of a given element decreases with temperature and its coefficient of resistivity is negative. Identify the element

7.      Explain why alloys are used tomake standard resistors

8.      State the SI unit of electrical energy

9.      Calculate the number of joules in 1KWh

10.  If a bulb of 100W gives light for 5 hrs, calculate number of electricity units used.