MCQ
The area of a ring having $'R\ ’$ as outer radius and $'r\ '$ as inner radius is :
- A$\pi(\text{R}+\text{r})$
- B$\pi(\text{R}-\text{r})$
- ✓$\pi(\text{R}^2-\text{r}^2)$
- D$\pi\text{(R}^2+\text{r}^2)$
✓
Answer
Correct option: C.
$\pi(\text{R}^2-\text{r}^2)$
The area of a ring having $'R\ ’$ as outer radius and $'r\ ’$ as inner radius is $\pi\text{R}^2 − \pi\text{r}^2 = \pi(\text{R}^2−\text{r}^2).$
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