Question

If the radius of a spherical balloon increases by 0.1%, then its volume increases approximately by

• A. 0.002
• B. 0.003
• C. 0.004
• D. 0.0005

Answer 1

Answer: (B)

0.003

Answer 2

$v = \frac{4}{3}\pi r^{2}, \,\because \,\Delta r = \left(\frac{0.1}{100}\right)r\,\therefore\,\Delta r = 4\pi r^{2}.\left(\frac{0.1}{100}\right)r = \left(\frac{0.3}{100}\right)v$