If the vectors A and B are of magnitude 4 and 3 cm making of 30° and 90° respectively with X- axis, their scalar product will be:
Correct answer: C. 6.0 cm2
- A. 0 cm2
- B. 18 cm2
- C. 6.0 cm2
- D. 21 cm2
Explanation
scalar product = dot product=A•B cos thetaθ = 90-30= 60cos 60=1/2so ABCos θ =3×4×1/2=6cm^2so ans is c )6cm^2
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About Vectors and Equilibrium
Vectors have magnitude and direction, unlike scalars, and are combined by head-to-tail or parallelogram methods. Work covers rectangular components, equilibrium when the resultant force is zero, the scalar product for work and projections, and the vector product for torque and cross-product direction using the right-hand rule.
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