Question

The vector  40î + 30ĵ is added to a vector. The result gives 15î + 3ĵ as the answer. The unknown vector is _____

(a) -25î – 27ĵ

(b) 25î + 27ĵ

(c) -25î + 27ĵ

(d) 25î – 27ĵ

The question was asked by my college director while I was bunking the class.

My enquiry is from Vector Addition topic in chapter Motion in a Plane of Physics – Class 11

Answer 1

Correct choice is (a) -25î – 27ĵ

The best I can explain: The required vector can be obtained by subtracting 40î + 30ĵ from 15î + 3ĵ. The result gives -25î – 27ĵ. One should pay attention on which vector has to be subtracted from which one.