Home › CBSE Class 11 › Physics › Motion in a Plane › Per NCERT §3.5, a vector A in 3D has components …
Per NCERT §3.5, a vector A in 3D has components along three orthogonal axes that satisfy which identity (with direction cosines cos α, cos β, cos γ)?
Atan α + tan β + tan γ = 0
Bcos²α + cos²β + cos²γ = 1
Ccos α + cos β + cos γ = 1
Dcos²α + cos²β + cos²γ = 0
Answer & Solution
Correct answer: B. cos²α + cos²β + cos²γ = 1
NCERT §3.5: A_x² + A_y² + A_z² = A² gives cos²α + cos²β + cos²γ = 1.
Related questions
The time for one full revolution is the:Centripetal acceleration has constant magnitude but is not a constant vector because its:Newton named the centre-directed acceleration:The acceleration in uniform circular motion always points:A car goes round a roundabout at a steady 20 km/h. Its motion is:For a fixed launch speed, range is greatest at a launch angle of:The horizontal distance from launch to where the projectile lands back at the same level iTime of flight is twice the time to reach maximum height because the path is: