A Spherical Party Balloon Is Being Inflated by Helium Pumped

question 43

Multiple Choice

A spherical party balloon is being inflated by helium pumped in at a rate 3 cubic feet per minute. How fast is the radius growing at the instant when the radius has reached 1 foot? The volume of a sphere of radius r is .

• A)0.64 feet per minute
• B)0.72 feet per minute
• C)0.76 feet per minute
• D)0.14 feet per minute
• E)0.24 feet per minute

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Definitions:

Pentaerythritol Tetranitrate

An explosive compound better known as PETN, used both in military and industrial applications, with a formula of C5H8N4O12.

Acronym

A word formed from the initial letters of a phrase, making it easier to remember or say.

Shockwave

A sharp change in pressure, temperature, and density moving through a medium, typically caused by an object moving faster than the speed of sound in that medium.

High Explosives

Substances that detonate, decomposing extremely rapidly and producing a shock wave with high energy output.