1. Class 12
2. Important Question for exams Class 12
3. Chapter 10 Class 12 Vector Algebra

Transcript

Misc 6 Find a vector of magnitude 5 units, and parallel to the resultant of the vectors ๐ โ = 2๐ ฬ + 3๐ ฬ โ ๐ ฬ and ๐ โ = ๐ ฬ โ 2๐ ฬ + ๐ ฬ. ๐ โ = 2๐ ฬ + 3๐ ฬ โ ๐ ฬ ๐ โ = ๐ ฬ โ 2๐ ฬ + ๐ ฬ (๐ โ + ๐ โ) = (2 + 1)๐ ฬ + (3 โ 2)๐ ฬ + (โ1 + 1)๐ ฬ = 3๐ ฬ + 1๐ ฬ + 0๐ ฬ Let ๐ โ = (๐ โ + ๐ โ) โด ๐ โ = 3๐ ฬ + 1๐ ฬ + 0๐ ฬ Magnitude of ๐ โ = โ(32+12+02) |๐ โ | = โ(9+1) = โ10 Unit vector in direction of ๐ โ = 1/|๐ โ | ร ๐ โ ๐ ฬ = 1/โ10 ร [3๐ ฬ+1๐ ฬ+0๐ ฬ ] ๐ ฬ = ๐/โ๐๐ ๐ ฬ + ๐/โ๐๐ ๐ ฬ + 0๐ ฬ Vector with magnitude 1 = 3/โ10 ๐ ฬ + 1/โ10 ๐ ฬ + 0๐ ฬ Vector with magnitude 5 = 5 ร [3/โ10 " " ๐ ฬ" + " 1/โ10 ๐ ฬ" + 0" ๐ ฬ ] = 15/โ10 ๐ ฬ + 2/โ10 ๐ ฬ + 0๐ ฬ = 15/โ10 ๐ ฬ + 2/โ10 ๐ ฬ Rationalizing = 15/โ10 ร โ10/โ10 ๐ ฬ + 2/โ10 "ร " โ10/โ10 ๐ ฬ = (15โ10)/10 ๐ ฬ + (2โ10)/10 ๐ ฬ = (3โ10)/2 ๐ ฬ + โ10/5 ๐ ฬ Hence the required vector is (๐โ๐๐)/๐ ๐ ฬ + โ๐๐/๐ ๐ ฬ

Chapter 10 Class 12 Vector Algebra

Class 12
Important Question for exams Class 12