Explore
Surface Area of Spheres Flashcards
GCSE Mathematics (Edexcel) 1MA1
Ready to master these flashcards?
Sign in to study with spaced repetition and track your progress.
Sign In to Track ProgressTerms in this set (10)
Surface area of a sphere formula
The surface area of a sphere is given by the formula 4πr², where r is the radius.
What does r represent in the formula 4πr²?
In the formula 4πr², r represents the radius of the sphere.
Unit of surface area
The surface area is measured in square units, such as cm² or m².
How to find the radius from the diameter
The radius is half the diameter. Divide the diameter by 2 to find the radius.
Effect of doubling the radius on surface area
If the radius is doubled, the surface area increases by a factor of 4 (since surface area is proportional to r²).
Surface area of a hemisphere
The surface area of a hemisphere is 2πr² for the curved surface, or 3πr² if the base is included.
Key step in solving surface area problems
Always ensure the radius is in the same unit as the desired surface area unit before substituting into the formula.
Surface area of a sphere with radius 5 cm
Using the formula 4πr², the surface area is 4π(5)² = 100π cm².
Real-life example of a sphere
Examples of spheres include a basketball, a globe, or a marble.
Common mistake when calculating surface area
A common mistake is forgetting to square the radius before multiplying by 4π.
Want to Learn More?
Get personalised lessons, quizzes, and instant feedback from your AI tutor.
Start Learning