come on plz?

Question

ok... how would i solve this:

Two 15-N forces act concurrently on point P. Find the magnitude of their resultant when the angle between them is:

a. 0.0
b. 30.0

Answer 1

At 0.0 degrees, the forces are additive. The result would be a 30 newton force on point P.

Forces are always added vectorily. If the forces were 180 degrees apart (opposite directions) they would cancel each other.

For (b) at 30 degrees, the forces would be

15 newtons + 15 (sin 30) newtons = 15 + 15(1/2) = 22.5 newtons

Answer 2

"Act concurrently" means that both forces are applied over point P.

The problem asks for the "resultant", which means that your job is to add up all force vectors applied over P.

Whenever you know the angle formed between two force vectors, they add up according to this eq.:

(vector1+ vector2) = sq. root of (v1²+ 2*v1*v2*cos(angle)+ v2²)

--- --- --- --- ---
a.
(vec1+ vec2) = sq. root of (15²+ 2*15*15*cos(0.0º)+ 15²) =
___ = sq. root of (900)
___ = 30

b.
(vec1+ vec2) = sq. root of (15²+ 2*15*15*cos(30.0º)+ 15²) =
___ = sq. root of (839.71)
___ = 28.97

Answer 3

for a: add them, i.e 30 N, if they act in same direction, subtract if they oppose.

b: F1+F2(sin 30)