Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main202126 Aug 2021Morning ShiftPhysicsMathematics in PhysicsActual

The magnitude of vectors OA → , OB → and OC → in the given figure are equal. The direction of OA → + OB → - OC → with x - axis will be:

Options

  1. Atan − 1 ⁡ ( 3 − 1 + 2 ) ( 1 + 3 − 2 )
  2. Btan − 1 ⁡ ( 1 − 3 − 2 ) ( 1 + 3 + 2 )
  3. Ctan − 1 ⁡ ( 3 − 1 + 2 ) ( 1 − 3 + 2 )
  4. Dtan − 1 ⁡ ( 1 + 3 − 2 ) ( 1 − 3 − 2 )

Correct answer

B. tan − 1 ⁡ ( 1 − 3 − 2 ) ( 1 + 3 + 2 )

Step-by-step solution

From the above diagram, the equations are, OA → = R cos 30 ∘ i ^ + sin 30 ∘ j ^ OB → = R cos 60 ∘ i ^ - sin 60 ° j ^ OC → = R - cos 45 ° i ^ + sin 45 ° j ^ ⇒ OA → + OB → − OC → = R 1 2 + 3 2 + 1 2 i ^ + R 1 2 − 3 2 − 1 2 j ^ , angle with the x - axis. ⇒ tan α = 1 2 − 3 2 − 1 2 1 2 + 3 2 + 1 2 = 1 − 3 − 2 1 + 3 + 2 ⇒ α = tan − 1 1 − 3 − 2 1 + 3 + 2 .

Practice Mathematics in Physics on Quantrex Academy →

More from Mathematics in Physics

The density of a uniform cylinder is determined by measuring its mass m , length l and diameter d . The measured values of m , l and d are 97.42 0.02 g, 8.35 0.05 mm and 20.20 0.02 2026Four persons measure the length of a rod as 20.00 ~cm , 19.75 ~cm , 17.01 ~cm and 18.25 cm. The relative error in the measurement of average length of the rod is : 2026In an experiment the values of two spring constants were measured as k₁=(10 0.2) N / m and k₂=(20 0.3) N / m . If these springs are connected in parallel, then the percentage error 2026Length, breadth and thickness of a strip having a uniform cross section are measured to be 10.5 cm , 0.05 mm , and 6.0 ~m , respectively. Which of the following option(s) give(s) t 2025A quantity Q is formulated as X ⁻² Y ^ + 3 2 Z ^ - 2 5 X , Y and Z are independent parameters which have fractional errors of 0.1,0.2 and 0.5 , respectively in measurement. The max 2025A physical quantity C is related to four other quantities p , q , r and s as follows C = pq ^2 r ^3 ~s The percentage errors in the measurement of p , q , r and s are 1 %, 2 % 3 % 2025A physical quantity Q is related to four observables a, b, c, d as follows : Q = ab ^4 ~cd where, a =(60 3) Pa ; b =(20 0.1) m ; c =(40 0.2) Nsm ⁻² and d =(50 0.1) m , then the per 2025For an experimental expression y= 32.3 1125 27.4 , where all the digits are significant. Then to report the value of y we should write 2025 Full Mathematics in Physics list All JEE Main PYQs