Question

5
Two forces act an angle of 120°. If the
greater force is 150 N and their resultant is
perpendic-ular to the smaller force, the
smaller force is​

Answer 1

Answer:

Step-by-step explanation:

Let the resultant force vector  FR→  is making an angle  900  with the smaller force  F1→.  This implies that the resultant makes an angle  α=120–90=300 with the bigger vector  F2→  as shown in the figure.

From the right angle triangle ACD, defining  sinα  we get

sinα=opposite sideadjucent side=DCAD  

AD=length of F2→=F2=40N  (given)

DC=length of F1→=F1=?  (to find out)

∴sin(300)=F1F2  

⇒F1=F2×sin(300)  

⇒F1=40×12  

⇒F1=20N