Quick summary
Cost accounting records, classifies and analyses costs so that management can find the cost of each product, job or service, control waste and fix prices. This first topic explains the meaning and objectives of cost accounting, the elements of cost, cost unit and cost centre, and the different ways of classifying costs.
Key points
- Cost (परिव्यय) – the amount of expenditure actually incurred on, or attributable to, a given thing.
- Costing – the technique and process of finding costs. Cost accounting – applying costing principles to record and control costs.
- Objectives: find cost per unit, help in price fixing, control costs, reduce waste, give data for decisions (make or buy, shut down), and help in budgets.
- Elements of cost: Material, Labour and Expenses. Each is direct (traced to one product) or indirect (overheads).
- Indirect material + indirect labour + indirect expenses = overheads, grouped as factory, office/administration, and selling & distribution.
- Cost unit – the unit in which cost is measured (per tonne of steel, per kWh of power, per passenger-km, per bed-day in a hospital).
- Cost centre – a location, person or machine for which costs are collected (production or service cost centre).
- Profit centre – a segment responsible for both cost and revenue.
- Classification of cost: by nature/element, by function (production, administration, selling, distribution, R&D), by behaviour (fixed, variable, semi-variable), by controllability (controllable, uncontrollable), by normality (normal, abnormal), by time (historical, pre-determined/standard), and for decisions (sunk, opportunity, marginal, differential cost).
- Financial vs cost accounting: financial accounts show the overall result for outsiders and are compulsory; cost accounts show product-wise cost for management and are needed by law only for certain industries under the Companies (Cost Records and Audit) Rules, 2014.
Important terms
- Fixed cost – stays the same in total when output changes (rent, salaries); cost per unit falls as output rises.
- Variable cost – changes in total in direct proportion to output (raw material); per unit it stays the same.
- Semi-variable cost – partly fixed, partly variable (electricity, telephone).
- Sunk cost – a past cost that cannot be recovered and is ignored in decisions.
- Opportunity cost – the benefit given up by choosing one option over the next best one.
Formats and formulas
- Prime cost = direct material + direct labour + direct expenses.
- Total cost = prime cost + all overheads.
- High–low method: variable cost per unit = change in cost ÷ change in output; fixed cost = total cost − (variable cost per unit × output).
Worked problem: At 1,000 units the power cost is ₹25,000; at 1,500 units it is ₹32,500. Find fixed and variable parts.
| Item | Working | Result |
|---|---|---|
| Change in cost | 32,500 − 25,000 | ₹7,500 |
| Change in output | 1,500 − 1,000 | 500 units |
| Variable cost per unit | 7,500 ÷ 500 | ₹15 |
| Fixed cost | 25,000 − (1,000 × 15) | ₹10,000 |
| Check at 1,500 units | 10,000 + (1,500 × 15) | ₹32,500 |
5 important questions
Q1. Define cost unit and cost centre with examples.
Cost unit is the unit of product or service in which cost is expressed, e.g. per tonne for cement, per km for transport. Cost centre is a location, person or equipment for which costs are collected, e.g. machine shop, packing department.
Q2. Give four examples each of direct and indirect material.
Direct: wood in furniture, cloth in shirts, steel in a car body, leather in shoes. Indirect: lubricating oil, cotton waste, small nails and glue, cleaning material.
Q3. Explain the classification of costs.
Outline: by element (material, labour, expenses); by traceability (direct, indirect); by function; by behaviour with a short graph description; by controllability; by normality; by time; for decision-making. Give one example under each.
Q4. Distinguish between cost accounting and financial accounting.
Points: purpose (management vs outsiders), legal need, scope (product-wise vs whole firm), period (frequent vs yearly), stock valuation (cost vs lower of cost or net realisable value), use of estimates, control of costs, form of reports.
Q5. At 2,000 units total cost is ₹60,000 and at 3,000 units ₹80,000. Find fixed cost and the cost at 3,500 units.
Variable cost per unit = 20,000 ÷ 1,000 = ₹20. Fixed = 60,000 − (2,000 × 20) = ₹20,000. Cost at 3,500 units = 20,000 + (3,500 × 20) = ₹90,000.
Exam tip
For a "classification of cost" question, draw a neat chart first and then explain each head with an example. It fetches full marks quickly.