trigonometry angles arc length hard class11 MCQ Questions for Class 11
trigonometry angles arc length hard class11 se related questions ko ek jagah revise karein. Har question me bilingual content, answer feedback aur explanation available hai.
B. \(\frac{14\pi}{3}\) सेमी/\(\frac{14\pi}{3}\) cm
Step 1
Concept
\(40^\circ=\frac{2\pi}{9}\) and \(s=21\times\frac{2\pi}{9}=\frac{14\pi}{3}\). In exams, convert degrees into radians and apply \(s=r\theta\).
Step 2
Why this answer is correct
The correct answer is B. \(\frac{14\pi}{3}\) सेमी / \(\frac{14\pi}{3}\) cm. \(40^\circ=\frac{2\pi}{9}\) and \(s=21\times\frac{2\pi}{9}=\frac{14\pi}{3}\). In exams, convert degrees into radians and apply \(s=r\theta\).
Step 3
Exam Tip
\(40^\circ=\frac{2\pi}{9}\) और \(s=21\times\frac{2\pi}{9}=\frac{14\pi}{3}\)। परीक्षा में डिग्री को रेडियन में बदलकर \(s=r\theta\) लगाएं।
\(s=r\theta\), so \(r=\frac{10\pi}{\frac{2\pi}{3}}=15\). In exams, multiply by the reciprocal while dividing by a fraction.
Step 2
Why this answer is correct
The correct answer is C. (15) सेमी / (15) cm. \(s=r\theta\), so \(r=\frac{10\pi}{\frac{2\pi}{3}}=15\). In exams, multiply by the reciprocal while dividing by a fraction.
Step 3
Exam Tip
\(s=r\theta\), इसलिए \(r=\frac{10\pi}{\frac{2\pi}{3}}=15\)। परीक्षा में भिन्न से भाग देते समय उल्टा गुणा करें।
\(80^\circ=\frac{4\pi}{9}\) radians and \(s=9\times\frac{4\pi}{9}=4\pi\). In exams, convert degrees into radians first.
Step 2
Why this answer is correct
The correct answer is C. \(4\pi\) सेमी / \(4\pi\) cm. \(80^\circ=\frac{4\pi}{9}\) radians and \(s=9\times\frac{4\pi}{9}=4\pi\). In exams, convert degrees into radians first.
Step 3
Exam Tip
\(80^\circ=\frac{4\pi}{9}\) रेडियन और \(s=9\times\frac{4\pi}{9}=4\pi\)। परीक्षा में डिग्री को पहले रेडियन में बदलें।
\(s=r\theta=5\times\frac{7\pi}{10}=\frac{7\pi}{2}\) cm. In exams, put the radian angle directly in the formula.
Step 2
Why this answer is correct
The correct answer is B. \(\frac{7\pi}{2}\) सेमी / \(\frac{7\pi}{2}\) cm. \(s=r\theta=5\times\frac{7\pi}{10}=\frac{7\pi}{2}\) cm. In exams, put the radian angle directly in the formula.
Step 3
Exam Tip
\(s=r\theta=5\times\frac{7\pi}{10}=\frac{7\pi}{2}\) सेमी। परीक्षा में रेडियन कोण को सीधे सूत्र में रखें।
For arc length, \(s=r\theta\), so \(\theta=\frac{s}{r}\). In exams, the angle in this formula is always in radians.
Step 2
Why this answer is correct
The correct answer is A. \(\frac{11}{14}\). For arc length, \(s=r\theta\), so \(\theta=\frac{s}{r}\). In exams, the angle in this formula is always in radians.
Step 3
Exam Tip
चाप लंबाई के लिए \(s=r\theta\), इसलिए \(\theta=\frac{s}{r}\)। परीक्षा में इस सूत्र में कोण हमेशा रेडियन में होता है।
