Question

If two vectors are equal and resultant is also equal to one of them then the angle between the two vectors is ​

Answer 1

Answer:

Let R , Q are two vector which magnitude is equal also resultant of it also equal to either

e.g | R | = | Q |

and resultant = R + Q

magnitude of resulatant = | R | = | Q|

so, | R | = | R + Q |

| R | = √( | R|² + | Q|² +2|R | |Q| cos∅)

take square of both sides

R² = R² + Q² + 2|R| |Q| cos∅

put | R| =|Q|

R² = R² + R² +2R² cos∅

cos∅ = -1/2

∅ = 2π/3

Answer 2

Answer:

60

Explanation:

2v² - 2v²cos∝ = v²

2 - 2cos∝ = 1

cos ∝ = 0.5

∝ = 60