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MathsMediumMCQ2022 ยท 24 Jun Shift 1

Q76.The surface area of a balloon of spherical shape being inflated, increases at a constant rate. If initially, the radius of balloon is 3 units and after 5 seconds, it becomes 7 units, then its radius after 9 seconds is (1) 9 (2) 7 (3) 5 (4) 3

What This Question Tests

The problem involves related rates, where the surface area of a spherical balloon increases at a constant rate, and requires integrating this rate to find the radius at a later time.

Concepts Tested

Related ratesSurface area of a sphereIntegration

Formulas Used

A = 4ฯ€rยฒ

dA/dt = constant

Integration of differential equations

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