Cosθi^ + Sinθj^ is a_________________?
Correct answer: D. The unit vector in the direction at angle θ with an x-axis
- A. Vector
- B. Position Vector
- C. Vector in the direction at angle θ with an x-axis
- D. The unit vector in the direction at angle θ with an x-axis
Explanation
The magnitude of cosθ i + sinθ j is sqrt(cos²θ + sin²θ) = sqrt1 = 1, so it is a unit vector. Its components give an angle θ with the positive x-axis because its x and y components are cosθ and sinθ. Option a is incomplete because it identifies only a vector, not the more specific unit-vector property.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Rectangular Components
A vector is resolved into perpendicular horizontal and vertical components using trigonometric relations, usually as Ax = A cos θ and Ay = A sin θ when θ is measured from the horizontal. Questions involve signs in different quadrants, reconstructing a resultant from components, and using components to analyse equilibrium.
Practise Vectors and Equilibrium
431 free Vectors and Equilibrium MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Rectangular Components questions
The unit vector in the direction of vector A = 2 i^ -2j^ + k^ is_______________?
In which quadrant, the only value of tan will be positive ?
In which quadrant the two rectangular components of a vector have same sign ?
Maximum number of rectangular components are_____________?
The rectangular coordinate system is also called______________?
If the force of magnitude 8 N acts on a body in direction making an angle 30, its X and Y components will be: