If vectors A=cos wti + sin wtj and B= cos wt/2 i + sin wt/2 j are functions of time,

⇦

⇨

If vectors A=cos wti + sin wtj and B= cos wt/2 i + sin wt/2 j are functions of time, then the value of t at which they are orthogonal to each other is

Options

(a) t = π/2w
(b) t = π/w
(c) t=0
(d) t = π/4w

Correct Answer:

t = π/w

Explanation:

Two vectors are,
A = cos ωt î + sin ωt ĵ
B = cos (ωt/2) î + sin (ωt/2) ĵ
For two vectors A and B to be orthogonal
A.B = 0
A.B = 0 = cos ωt.cos (ωt/2) + sin ωt.sin (ωt/2)
= cos [ωt – (ωt/2)] = cos (ωt/2)
So, ωt/2 = π/2
.·. t = π/ω.

Related Questions:

1. In Bohr model of hydrogen atom, the force on the electron depends on the principal
2. The conductivity in the intrinsic semiconductor does not depend on
3. The refracting angle of a prism is A and refractive index of the material of the prism
4. In a photoelectric effect experiment, the slope of the graph between the stopping
5. A particle executes simple harmonic oscillations with an amplitude

Topics: Motion in Plane (93)
Subject: Physics (2479)

---

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

---

Share this page with your friends