Answer:
98 π R
Step-by-step explanation:
Surface area of sphere = 4 π R²
= 2 π R × 2 R
= 49 π × 2 R
= 98 π R
Answer:
(B) The magnitude is 7sqrt2, and the direction angle is approximately 135 degrees.
Step-by-step explanation:
From the figure, the coordinate of the tail of the vector,
The coordinate of the head of the vector,
The magnitude of a vector is the length between the head and tail of the vector.
By using the distance formula,
the magnitude of the vector
Now, let be the angle made by the vector with the positive direction of the x-axis, so
So, the magnitude of the vector is which makes with the positive direction of the x-axis.
Hence, option (B) is correct.
Answer: The answer is C. $20.00
Step-by-step explanation:
9514 1404 393
Answer:
8000π mm^3/s ≈ 25,133 mm^3/s
Step-by-step explanation:
The rate of change of volume is found by differentiating the volume formula with respect to time.
V = 4/3πr^3
V' = 4πr^2·r'
For the given numbers, this is ...
V' = 4π(20 mm)^2·(5 mm/s) = 8000π mm^3/s ≈ 25,133 mm^3/s
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<em>Additional comment</em>
By comparing the derivative to the area formula for a sphere, you see that the rate of change of volume is the product of the area and the rate of change of radius. This sort of relationship will be seen for a number of different shapes.