Question

pls answer my questions

three forces 9N 12N and 15N are acting at a point keep it in equilibrium, then the angle between 9N and 15N is....???​

Answer 1

Answer:

54°

Explanation:

By observation we find that the 3 number form a pythagoras triplet

ie

15²=12²+9²

Therefore

12 and 9 are the height and base respectively

so

cosx=9/15

cosx=3/5

therefore

x=cos⁻¹3/5

=54

where x=angle between 9 and 15

Aliter:

we know that the resultant force is given by

F=√(F1²+F2²+2F1F2cosx)

15²=12²+9²+2*12*9*cosx

2*12*9*cosx=0

this is only possible if

cosx=0

therefore

x=π/2

now the angle between 9 and 15 is

cosy=9/15

cosy=3/5

therefore

y=cos⁻¹3/5

=54

Hope this helps.

Answer 2

Answer:

8273=3+3+4+3+3+38293

Hope helps mate