Question

At what angle be the two force 2 and 2^1/2 acts so the resultant force has magnitude 10^1/2​

Answer 1

Let F1=2

And F2=√2

Resultent=√10

Let the angle == T

here we know,R=√(A²+B²+2ABcosT)

So,in our case,

√10=√(2²+√2²+2.2.√2cosT)

Kick the root from both side

→10=4+2+4√2cosT

→10=6+4√2cosT

→10-6=4√2cosT

→4=4√2cosT

→4÷4√2=cosT

→1/√2=cosT

Here we know,cos45°=1/√2

so,

→cos45°=cosT

→T=45°,

Ans....

SO the angle is 45°