Q. The volume of a right cone is 343π units 3. If its height is 21 units, find its radius.Answer: units
Volume Formula Application: The formula for the volume of a right cone is V=31πr2h, where V is the volume, r is the radius, and h is the height of the cone. We are given the volume V=343π units3 and the height h=21 units. We need to solve for the radius r.
Substitute Given Values: First, let's plug in the given values into the volume formula: 343π=(31)πr2(21).
Simplify Equation: To solve for r2, we can simplify the equation by dividing both sides by π, which gives us 343=(31)r2(21).
Eliminate Fraction: Next, we can multiply both sides by 3 to get rid of the fraction: 3×343=r2(21).
Calculate Value: Now, we calculate 3×343, which equals 1029. So, we have 1029=r2(21).
Isolate r2: To isolate r2, we divide both sides by 21: 211029=r2.
Calculate Square Root: Calculating 1029/21 gives us 49=r2.
Final Radius Calculation: Finally, to find r, we take the square root of both sides: 49=r.
Final Radius Calculation: Finally, to find r, we take the square root of both sides: 49=r.The square root of 49 is 7, so r=7 units.