Question

The radius of a circular plate is 1.05 m. Its area (in $m^2$) up to correct significant figures is

• A. 3.47
• B. 3.475
• C. 3.467
• D. 3.82
• E. 3.825

Answer 1

The Correct Option is B

The area \( A \) of a circular plate is given by the formula:

\[ A = \pi r^2 \] 

Where: - \( r \) is the radius of the circular plate, which is given as 1.05 m. Substituting the value of \( r = 1.05 \) m into the formula: \[ A = \pi \times (1.05)^2 = \pi \times 1.1025 \] Using \( \pi \approx 3.1416 \): \[ A \approx 3.1416 \times 1.1025 = 3.475 \] The radius is given to 3 significant figures, so the area should also be reported to 3 significant figures. Thus, the correct area, rounded to the correct significant figures, is 3.475 m².

Correct Answer:

Correct Answer: (B) 3.475