
Surface Area of Cylinder: Formula & GCSE Examples
The cylinder’s surface area splits into two parts you calculate separately: the curved side and the two circular ends. The formula 2πr(h+r) packages both components together for exams, but knowing where each term comes from makes the math stick. This guide covers the total surface area and curved surface area formulas, GCSE-style examples, and plain-language explanations for students and parents.
Total Surface Area Formula: 2πr(h + r) · Curved Surface Area Formula: 2πrh · Base Area (one): πr²
Quick snapshot
- Formula: 2πr(h + r) (The Knowledge Academy)
- Includes curved side + two bases (The Knowledge Academy)
- Use for closed cylinders (The Knowledge Academy)
- Lateral surface = rectangle (circumference × height) (Cuemath)
- Two circular bases add 2πr² (Cuemath)
- TSA = 2πrh + 2πr² = 2πr(r + h) (Cuemath)
- r = 9 cm, h = 13 cm (GCSE Maths YouTube)
- TSA = 2π × 9(9 + 13) = 1,243.86 cm² (GCSE Maths YouTube)
- CSA = 2π × 9 × 13 = 734.76 cm² (GCSE Maths YouTube)
What is the formula for the surface area of a cylinder?
The total surface area (TSA) of a closed cylinder accounts for every exposed face: the curved side and both circular ends. The formula is A = 2πr(r + h), where r is the radius and h is the height (The Knowledge Academy). This compact form packs together two components you calculate separately: the curved surface area and the combined area of both bases.
Total surface area
TSA = 2πrh + 2πr². The first term gives the lateral (curved) area; the second accounts for the two circles. You can factor this as 2πr(r + h) for shorter handwriting during exams.
Curved surface area (CSA)
CSA = 2πrh, which covers just the side. This is the formula you’ll reach for when a cylinder has an open top, a missing base, or when the question explicitly asks for “area of curved surface” only.
Open cylinder variations
An open-top cylinder drops one base. The formula becomes πr² + 2πrh, or πr(r + 2h) (Cuemath). A tin can without a lid is the real-world example.
The takeaway is that TSA always includes two bases, CSA never does, and the open-top version sits in the middle with just one. Mixing these up costs marks on GCSE papers.
What is the CSA surface area of a cylinder?
CSA stands for Curved Surface Area — the wrapping paper, so to speak, that goes around the middle of the cylinder. The formula CSA = 2πrh gives you the lateral surface only, excluding any circular ends (Cuemath). This matters in GCSE questions when you’re asked specifically for the curved surface, or when calculating material needed for a pipe or tube that has no lids.
Formula breakdown
Think of it this way: if you could unroll the curved side of a cylinder and lay it flat, it becomes a rectangle. The rectangle’s long side equals the circumference of the circle (2πr), and its short side is the cylinder’s height (h). Area of rectangle = length × width, which gives you 2πr × h = 2πrh (Study.com).
Difference from total surface area
TSA adds the two bases back in: TSA = CSA + 2πr² (Cuemath). The difference is always 2πr² — the combined area of both circular ends. For a cylinder with r = 7 cm and h = 14 cm, CSA = 2 × 3.14 × 7 × 14 = 615.8 cm².
A paint roller needs only CSA coverage, not TSA. A sealed container needs TSA. Knowing which one the question asks for determines whether you stop after 2πrh or carry on to add 2πr².
How do you calculate the surface area of a cylinder?
Calculating surface area involves three steps: measure the radius and height, apply the formulas, and add the components together (The Knowledge Academy). The process works whether you’re after total surface area or just the curved part.
Step-by-step with radius and height
Start by confirming your radius and height are in the same units. Then: step one, find the area of the two bases: 2πr². Step two, find the curved surface: 2πrh. Step three, add them together for TSA. Using r = 3 in and h = 15 in with π = 3.14: base area = 2 × 3.14 × 9 = 56.55 in²; curved area = 2 × 3.14 × 3 × 15 = 282.74 in²; TSA = 339.29 in² (Study.com).
Using diameter
If the question gives you diameter instead of radius, halve it first: r = d ÷ 2. The formula stays the same, but you need the radius for the calculation. Some textbooks use the form πDh + 2πr² directly from the diameter, where D = 2r (GCSE Maths YouTube).
In terms of pi
Leaving answers in terms of π means you don’t substitute 3.14 until the end — or sometimes not at all. For r = 5 ft and h = 100 ft: TSA = 2π(5)(5 + 100) = 2π × 525 = 1,050π ft². Approximated with π ≈ 3.14, that’s 3,297 ft² (Study.com).
Exact answers leave π symbolic; approximate answers use 3.14 and give a decimal. GCSE papers typically accept either form, but check the mark scheme for your specific exam board.
How to find the surface area of a cylinder for kids?
The visual approach works best for younger learners: imagine peeling the label off a tin can and laying it flat. What shape is it? A rectangle, of course. The label’s length equals the can’s circumference, and its height is the same as the can’s height (Cuemath). The ends of the can are circles — like the pepperoni on two pizzas.
Visual unrolling explanation
Draw a cylinder (or use a toilet paper roll). Cut the curved surface straight down and open it flat. The result is a rectangle. Measure its sides: one side is the height, the other is the circumference (2πr). Then find the area of the two circles separately using πr² and add everything together.
Simple examples
Take r = 7 m and h = 10 m. The curved area = 2 × 3.14 × 7 × 10 = 439.6 m². That’s the label area on your tin can — now you know how much paper you need to cover it. The two ends add another 2 × 3.14 × 7² = 307.9 m², giving a total of 747.5 m².
What is the surface area of a cylinder GCSE?
GCSE Maths tests surface area from Foundation to Higher tier, typically for students aged 14 and above (GCSE Maths YouTube). The standard formula is 2πr(r + h), and exam questions often give radius and height directly or ask you to find them first from a diameter or circumference.
GCSE-specific formulas
Total surface area: A = 2πr² + 2πrh or A = 2πr(r + h). Curved surface area: A = 2πrh. Open-top: A = πr² + 2πrh. You might also see it as πDh for the curved part (where D = diameter) — this is equivalent to 2πrh since D = 2r (GCSE Maths YouTube).
Exam examples
For the common GCSE example r = 9 cm, h = 13 cm: curved surface = 2π × 9 × 13 = 734.76 cm²; bases = 2 × π × 9² = 508.94 cm²; total = 1,243.70 cm². Using the compact formula: TSA = 2π × 9(9 + 13) = 1,243.70 cm².
The implication for GCSE students is that showing your working matters. Write out 2πrh + 2πr², substitute the numbers, and arrive at your answer — each step earns credit, and the formula itself is worth remembering in both its expanded and factored forms.
GCSE questions that ask for surface area almost always expect the total surface area including both bases, unless they specify “curved surface area” or mention an open-top container.
Worked example: r = 15 cm, h = 7 cm
This is a standard GCSE-style question, often appearing in past papers. Given a cylinder with radius 15 cm and height 7 cm, find the total surface area.
- Step 1: Confirm units match — both in centimetres, so you’re good to proceed.
- Step 2: Calculate curved surface area: CSA = 2πrh = 2 × π × 15 × 7 = 210π cm² ≈ 659.73 cm².
- Step 3: Calculate base areas: 2 × πr² = 2 × π × 225 = 450π cm² ≈ 1,413.72 cm².
- Step 4: Add curved + bases: TSA = 210π + 450π = 660π cm² ≈ 2,073.45 cm².
Using the compact formula: TSA = 2πr(r + h) = 2π × 15 × (15 + 7) = 2π × 15 × 22 = 660π cm².
Upsides
- Formula is consistent across all cylinder types
- Unrolling visual makes CSA intuitive for beginners
- GCSE exam questions follow predictable patterns
- Can leave answers in terms of π for exact results
Downsides
- Mixing up TSA and CSA loses marks on exams
- Diameter-to-radius conversion adds a potential error point
- Using wrong units or mixing them causes incorrect answers
- Forgetting one of the two bases undercounts TSA
The surface area (also known as the total surface area) of a cylinder of radius ‘r’ and height ‘h’ is 2πr(r+h). — Cuemath (Math Education Platform)
TSA=2πrh+2πr²=2(3.14)(3)(15)=282.74+56.55=339.29 in². — Study.com (Education Platform)
The pattern that emerges across GCSE resources is straightforward: surface area problems follow a predictable structure. Identify what you’re measuring (curved, total, or open-top), apply the corresponding formula, and show each step in the working. The formulas are locked in, but the skill is in selecting the right one and executing without unit or component errors.
How to calculate surface area of cylinder with diameter?
Divide the diameter by 2 to get the radius first, then use the standard formulas. If diameter = 10 cm, then r = 5 cm. From there, TSA = 2πr(r + h) and CSA = 2πrh apply as normal.
What is surface area of cylinder volume?
Volume and surface area are separate measurements. Volume of a cylinder = πr²h; surface area = 2πr(r + h). A question that mentions volume is asking about a different property — don’t confuse the two formulas.
Surface area of cylinder example problems?
Common GCSE examples include r = 9 cm, h = 13 cm (TSA = 1,243.86 cm²) and r = 15 cm, h = 7 cm (TSA ≈ 2,073.45 cm²). Both require finding curved area plus two bases.
How does volume of cylinder relate to surface area?
They share the radius (r) and height (h), but that’s where the similarity ends. Volume measures interior capacity (πr²h); surface area measures exterior coverage. They’re calculated independently.
Surface area of cylinder corbettmaths solutions?
Corbettmaths provides exam-style practice questions with worked solutions. Their resources typically use r and h values like r = 9 cm and h = 13 cm, matching the standard GCSE examples found in past papers.
Formula for surface area of open cylinder?
An open-top cylinder has one base instead of two: surface area = πr² + 2πrh, or πr(r + 2h). This applies to cans without lids, cups, and other open containers.
Surface area of cylinder in terms of pi?
Leave π symbolic throughout: TSA = 2πr(r + h). For r = 5 and h = 10, TSA = 2π × 5 × 15 = 150π. This is the exact answer; using π ≈ 3.14 gives 471.23 as the approximate decimal.
For students revising for GCSE Maths, the decision is clear: learn both formulas (2πr(r + h) for total and 2πrh for curved), practice the unit conversion step, and show every step of working on exam day. For parents checking homework, the visual unrolling method — cutting open a toilet paper roll — is the fastest way to explain why the curved part becomes a rectangle.
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GCSE students tackling cylinders with r=9cm and h=13cm can benefit from reviewing the formula 2πr(h+r) alongside GCSE surface area walkthroughssimilar step-by-step examples.