Track Plane: Find $\hat R_{BA}$ (2 SF)

  • Thread starter Thread starter EaGlE
  • Start date Start date
  • Tags Tags
    Plane Tracking
AI Thread Summary
The discussion focuses on calculating the change in the displacement vector, \hat R_{BA}, for an airplane tracked by a radar station. Initial observations at point A show the plane at a range of 360 m and an elevation of 40 degrees, while at point B, the range is 880 m directly overhead. The calculations confirm that the displacement vectors at points A and B can be expressed as (274.7, 231.5) and (0, 880), respectively. By subtracting these vectors, the change in displacement vector is determined to be (-270, 650) when rounded to two significant figures. The final answer for \hat R_{BA} is thus (-270, 650).
EaGlE
Messages
20
Reaction score
0
Intro: A radar station detects an airplane coming straight at the station from the east. At first observation (point A), the range to the plane is 360 m at 40 degrees above the horizon. The plane is tracked for another 123 degrees in the vertical east-west plane for 5.0 s, until it has passed directly over the station and reaches point B. The range at final contact is 880 m. The contact points are shown in the diagram.

Question: What is \hat R_{BA} the change of the displacement vector of the plane while the radar was tracking it?

Here, \hat R_{BA} = \hat R_{B} - \hat R_{A}. Express \hat R_{BA} numerically as an ordered pair, separating the x and z components with a comma, to an accuracy of two significant figures.


my work is also included(work i did is in red)... did i do my calculations correctly?
 

Attachments

  • physics.jpg
    physics.jpg
    3.2 KB · Views: 3,544
  • mywork.JPG
    mywork.JPG
    4.9 KB · Views: 4,527
Last edited:
Physics news on Phys.org
everything looks good except you didn't quite answer the question! the answer should be in the form r = <dx, dy>.
 


Yes, your calculations appear to be correct. The change in the displacement vector, \hat R_{BA}, can be calculated by subtracting the initial displacement vector at point A from the final displacement vector at point B. This can be done by breaking down the displacement vectors into their x and z components and then subtracting them.

At point A, the displacement vector can be represented as (360cos(40), 360sin(40)) = (274.7, 231.5). Similarly, at point B, the displacement vector can be represented as (0, 880) = (0, 880).

Subtracting the x components, we get 0 - 274.7 = -274.7 and subtracting the z components, we get 880 - 231.5 = 648.5.

Therefore, the change in displacement vector, \hat R_{BA}, is (-274.7, 648.5) to two significant figures. This can also be represented as an ordered pair as (-270, 650).

So, the answer to the question would be:

\hat R_{BA} = (-270, 650)
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top