NCERT Class 12 · Ch 10 Exercise 10.3 · Q8
NCERT Class 12 Maths · Chapter 10 Vector Algebra · Exercise 10.3 Question 8
Vectors a,b have equal magnitude, angle 60° and a·b=1/2. Find their magnitudes.
💡 Concept Hints
- Write the vector components and identify the required direction or geometric relation.
- Use the magnitude, dot-product, cross-product or section formula that matches the requested quantity.
✅ Step-by-Step Solution
Final Answer: Both magnitudes are 1.
- Let the common magnitude be r≥0. Then a·b=r²cos60°=r²/2.
- Equate this to 1/2 to get r²=1, hence r=1.
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