Recent content by Remle

  1. Remle

    Finding the angle of a resultant vector with the law of sines

    @kuruman @PeroK Yeah, sorry for not showing work. Here it is: If ##\text{vector-15}## is along the ##x\text{-axis}##, then: $$\theta = \sin^{-1} {(\frac {15 \sin{140}} {47})}$$ $$\theta = \text{28°}$$ If ##\text{vector-35}## is along the ##x\text{-axis}##, then: $$\theta = \sin^{-1} {(\frac {35...
  2. Remle

    Finding the angle of a resultant vector with the law of sines

    Using your diagram and ##x\text{-axis}## for the reference angle I get 28 degrees. Am I right?
  3. Remle

    Finding the angle of a resultant vector with the law of sines

    I know is asking only for the magnitude of the vector. I believe the question is, which vector connects head-to-tail to whom to get the angle from the ##x\text{-axis}##?
  4. Remle

    Finding the angle of a resultant vector with the law of sines

    So, for this problem is difficult to say? Does it need to specify which force is the first one? I, most of the time, choose the ##x\text{-axis}## as a reference but that too gave me 12 degrees and 28 degrees.
  5. Remle

    Finding the angle of a resultant vector with the law of sines

    Ok. My problem is what angle to choose when adding vector. Statement does not tell me which one is the "first" force vector. So, when using the law of sine formula I get two results. First, using cosine to get the magnitude: $$\vec c = \sqrt{a^2 + b^2 +2ab\cos\theta},$$ $$\vec c = \sqrt{15^2 +...
  6. Remle

    Net displacement with signed distances: which formula to use?

    Sorry for the late response. For the distance since is a scalar just had to add all the numbers. ##d = 1.3 + 2.5 = 3.8~\rm{km}##.
  7. Remle

    Net displacement with signed distances: which formula to use?

    THIS is what I needed. So first displacement is ##\Delta d = 1.3 - 0## and the second is ##\Delta d = 0 - 2.5## so to speak.
  8. Remle

    Net displacement with signed distances: which formula to use?

    I having a little bit of problem with ##\Delta d = d_f - d_i##. When substituting fo ##d_f## and ##d_i##, should I follow the signs rule (positive or negative)? For example, The problem shows that the displacement is ##1.2~\rm{km}, south## by solving ##\Delta d = -2.5 + 1.3## and I get that, but...
  9. Remle

    Why do I get 8 m/s² instead of 4 m/s² for box acceleration?

    OMG... feel dumb. The ## 200~N ## is already the diagonal force. So the only thing I have to do is find ## F_\rm{ay} ## and it add to ## F_\rm{g} ##. Then only force left is ## F_\rm{ax} ## which that gives me ## 100~N ## dividing that with ## 25~\rm{kg} ## provides the ## 4~\rm{m/s^2} ##...
  10. Remle

    Why do I get 8 m/s² instead of 4 m/s² for box acceleration?

    $$F_\rm{a_\rm{y}} = -200 \times \sin(60) = -173.205~N$$ $$F_\rm{a_\rm{x}} = 200 \times \cos(60) = 100~N$$ $$F_\rm{g}= 25 \times -9.81=-245.25~N$$ $$F_\rm{Net_\rm{y}} = - 245.25 - 173.205 + 245.25 = -173.205~N$$ $$F_\rm{Net_\rm{x}} = 100~N$$ $$F_\rm{Net}=\sqrt{{(-173.205)^2} + 100^2} = 200.00~N$$...
  11. Remle

    Why do I get 8 m/s² instead of 4 m/s² for box acceleration?

    The problem does not say anything about a surface, so I just assumed it because that's how a normal force works. When I say original is I calculate FN with mass and gravity. Then I start adding or substracting other forces (if there's any) to this FN. Fg=245.25N and Fay=-173.205 N
  12. Remle

    Why do I get 8 m/s² instead of 4 m/s² for box acceleration?

    What is the acceleration of the box? Paper says the answer is 4 m/s2. What is the Normal force acting on the box? Paper says the answer is 418 N. I know that for most cases FN=Fg=W. So, by definition the "original" Normal force is 245.25 N (am I correct?) I calculated the Fay which is...
  13. Remle

    Can a Math Teacher Successfully Transition into Physics?

    First of all, thanks for accepting me! Math teacher by profession, but recently I've been getting into the area of physics. PF has helped me in many situations so I've decided to finally join the club and keep learning.