Question

When two forces f1 and f2 are applied in the same direction, their resultant is 30 N. If the forces are applied at an angle 90 with each other, their resultant is 5root26. If the forces are applied at an angle 60 with each other, their resultant (in Newton) is:

Answer 1

Answer:

Land resources mean the resources available from the land, thus the agricultural land which contain natural fertilizer for growth of the products sown; the underground water, the various minerals like coal, bauxite, gold and other raw materials.

Answer 2

The resultant of two forces when θ = 60° is 5√31 N.

Given:

Let f1 and f2 be the two forces

R = 30 N, when θ = 0°

R = 5√26 N, when θ = 90°

To Find:

The resultant of two forces when θ = 60°

Solution:

We know, that the resultant R² = f₁² + f₂² +2f₁f₂cosθ

i) when θ = 0

900 =  f₁² + f₂² +2f₁f₂ -----(1)

ii)when θ = 90

650 =  f₁² + f₂² --------(2)

iii) when θ = 60

R² = f₁² + f₂² +2f₁f₂cos60

    = f₁² + f₂² +(2f₁f₂/2)

    = f₁² + f₂² +f₁f₂ ---------(3)

Now substitute equation (2) in (1) and we get

2f₁f₂ = 900 - 650

       = 250

f₁f₂ = 125 ------- (4)

Now substitute equations (4) and (2) in (3) and we get

R² = 650 +125

    = 775

R = √775

  = 5√31 N

Therefore, The resultant of two forces when θ = 60° is 5√31 N.

#SPJ2