University:
Cypress College
Course:
PHYS 201 C | College Physics I
Academic year:

2021
Views:

19

Pages:

11
Author:

NikkiP24

Chapter 2: Mathematical Methods EXERCISES PAGE 29 Exercises Q1. (1) | Page 29 Choose the correct option. The resultant of two forces 10 N and 15 N acting along +x and-x-axes respectively, is 1. 25 N along + x-axis 2. 25 N along-x-axis 3. 5 N along x-axis 4. 5 N along-x-axis SOLUTION 5 N along-x-axis Exercises Q 1. (ii)| Page 29 Choose the correct option. For two vectors to be equal, they should have the 1. same magnitude 2. same direction 3. same magnitude and direction 4. same magnitude but opposite direction SOLUTION same magnitude and direction Exercises | Q1. (iii) | Page 29 Choose the correct option. The magnitude of scalar product of two unit vectors perpendicular to each other is 1. zero 21 3. -1 4. 2 SOLUTION zero Exercises Q1. (iv) | Page 29 Choose the correct option. The magnitude of the vector product of two unit vectors making an angle of 60q with each other is 1 2 3/2 √3 2 SOLUTION √3 2 Exercises | Q1. (v) | Page 29 Choose the correct option. If A, B and C are three vectors, then which of the following is not correct? A.(B+C) - AB+ A. AB-BA AXB-BXA Ax (BX)=AxB+BX SOLUTION AXB-BXA Evertises Q2.Page 29 Answer the following question. Show that a is a unit vector. √2 SOLUTION Let & be unit vector of sa. Now. -√2+3=√(5)²+()=1 a a itself is a unit vector. Q2.Page 29 Answer the following question. If-31+4j+k and 2-1-j-k determine the magnitude of +2. SOLUTION 1+2=(3+4+k)+(1-3) -31+1+4j -41+3j Magnitude of (+), 71+242 +32= √25 = 5 units - Magnitude of 1+2 is 5 units GZ Page 29 Answer the following question. For-21-3j and V-61+5j, determine the magnitude and direction of 1 SOLUTION 1+2-(2-3)+(-6i +5j) - (21-6j) + (-31 +5j) --41+23 1+2=(-4)²+22= √20-√4×5=2√5 Comparing 2 with R-R₂i+Ryj R₁-4 and R, = 2 Taking & to be angle made by R R with X-axis, = tan() = tan(3) = tan(-) with X-axis Eneries Q2. Ov | Page 29 Answer the following question. Find a vector which is parallel toi2j and has a magnitude 10. SOLUTION When two vectors are parallel, one vector is scalar multiple of another, Le, if and ware parallel then, wn where, n is scalar. This means, wnvxi + nvyj ni-2nj (VzL, Vy = 2) (n)²+(-2)² = √5n