Question

1. If y-component of vector (in x-y plane) having
magnitude 20 unit is 12 unit, then x-component of vector is
(1) 16 unit
(2) 8 unit
(3) 4 units
(4) 3 unit​

Answer 1

Answer:1) 16 unit

Explanation:

The angle b/w x-component and y-component is 90°

Using the eqn. ,

R = √x^2 + y^2 + 2xy cos90°

R= √x^2 + y^2

20 = √ x^2 + (12)^2

Squaring both sides,

400 = x^2 + 144

x^2 = 256

x = 16 unit