Question

The value of $[a-bb-cc-a]$ is

• A. 0
• B. 1
• C. 2
• D. 3

Answer 1

Answer: (A)

$1\times {10}^{-6}=3.14\times {10}^{-3}\times 2\times r\times {10}^{-2}$ $r=\frac{{10}^{-6}}{3.14\times {10}^{-5}\times 2}$ $=0.016m=1.6cm$ $\frac{C_1}{C_2}=\frac{\sin i}{\sin r}$ $\frac{3\times {10}^8}{c_2}=\frac{\sin {45}^o}{\sin {30}^o}=\frac{0.707}{0.5}$ $C_2=\frac{3\times {10}^8\times 0.5}{0.707}$