Help with Combining Oblique Vectors

  • Thread starter Thread starter Ferny84
  • Start date Start date
  • Tags Tags
    Vectors
AI Thread Summary
The discussion revolves around the combination of oblique vectors R, Q, and S, with specific magnitudes and angles. The initial calculations for the components of each vector were performed, leading to a resultant vector calculation. An error was identified in the handling of vector S, where the x-component was mistakenly considered zero instead of 2.15. Correcting this oversight resulted in the correct magnitude and angle for the resultant vector. The final answer confirmed was 1.67 at an angle of 99.68°, highlighting the importance of accurately accounting for all vector components.
Ferny84
Messages
3
Reaction score
0

Homework Statement


R = 3.5N[350] Q = 2.75N[125] S = 2.15N[0]

R + Q - S

The Attempt at a Solution



Finding x and y for 3.5N[350]
Sin80 = y/3.5 = -3.45
Cos80 = x/3.5 = 0.61

y = -3.45
x = 0.61

Finding x and y for 2.75N[125]
Sin35 = x/2.75 = -1.58
Cos35 = y/2.75 = 2.25

x = -1.58
y = 2.25

Finding x and y for 2.15[0]
x = 0
y = 0
(Since it's at 0)

Rx = 0.61 - 1.58
Rx = -0.97

Ry = -3.45 + 2.25
Ry = -1.2

a^2+b^2 = c^2
c=1.54

Tanθ=0.97/1.2
θ=39°

When I check the answer, it shows 1.67[99.68°] instead of my answer 1.54[39°].

What did I do wrong?
 
Physics news on Phys.org
Solved it...forgot that 2.15[0] had a x..which is 2.15.
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...

Similar threads

Back
Top