Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
AP EAMCET2011PhysicsMathematics in Physics

A certain vector in the x y -plane has an x -component of 4 ~m and a y -component of 10 ~m . It is then rotated in the x y -plane so that its x -component is doubled. Then its new y -component is (approximately)

Options

  1. A20 ~m
  2. B7.2 ~m
  3. C5.0 ~m
  4. D4.5 ~m

Correct answer

B. 7.2 ~m

Step-by-step solution

Here, A =4 i +10 j aligned | A |= (4)^2+(10)^2 & = 16+100 & = 116 ~m aligned Now, according to question, So, aligned A & =8 i +n j | A | & = (8)^2+n^2 116 & = (8)^2+n^2 aligned squaring both sides aligned 116 & =64+n^2 or n^2 & =116-64=52 or n & =7.2 ~m aligned

Practice Mathematics in Physics on Quantrex Academy →

More from Mathematics in Physics

Which of the following statements is/are true? (A) Three vectors not lying in a plane give zero resultant (B) Three vectors lying in a plane can give zero resultant (C) Two vectors 2026Forces A and B act at a point. The sum of their magnitudes is 50 N and the magnitude of their resultant is 20 N. If the resultant is at 90^ with the smaller force, the magnitudes o 2026If two vectors A = 4 i + n j + 2 k and B = 2 i + 2 j - k are mutually perpendicular to each other then value of 'n' is 2026A physical quantity x is related as x = a b^2 c^3 d⁻⁴ . Relative errors in the quantities a , b , c and d are 2%, 1%, 3% and 4% respectively. Relative error in x will be 2026The percentage error in the measurement of mass of a body and its speed are 0.73 % and 1.84 % respectively. The percentage error in the measurement of its momentum and kinetic ener 2026The area of parallelogram formed by vectors P = 2 i - j + 5 k and Q = 3 i - 2 j + 4 k is 2026A cuboid has volume V = l l l , where l is the length of one side. When the length l is measured by a meter scale of least count 1 , mm , the relative percentage error in the measu 2026For two vectors P and Q , P Q = | P Q | The magnitude of R = P + Q is ( 45^ = 1 2 ) ? 2026 Full Mathematics in Physics list All AP EAMCET PYQs