1. An airplane flies 210 km due west from city A to city B and then 312 km in the direction of 35.0° north of west from city B to city C.
I can't get the picture in my mind
2. Fox Mulder is trapped in a maze. To find his way out, he walks 10.0 m, makes a 90.0° right turn, walks 5.00 m, makes another 90.0° right turn, and walks 6.50 m. What is his displacement from his initial position?
Magnitude
3.While exploring a cave, a spelunker starts at the entrance and moves the following distances. She goes 75 m north, 250 m east, 135 m at an angle 30° north of east, and 125 m south. Find the resultant displacement from the cave entrance.
Magnitude
I solved the second one but I am unable to solve the first and third.
I don't quite understand what you would find hard.
Is it the term 35 degrees north of west?
For example, problem 2 does not use this, but 1 and 3 do.
Let's say we are traveling in a westerly direction.
?
\ North
x \ |
West -------EAST
|
South
Is it the term 35 degrees north of west?
For example, problem 2 does not use this, but 1 and 3 do.
Let's say we are traveling in a westerly direction.
CODE
?
\ North
x \ |
West -------EAST
|
South
We can go directly west, or westerly at any angle between north and south.
Let's say we go at an an angle between North and West. That would be North of west (as marked by the ?).
If the angle (x) between directly West and the direction we go is 35 degrees, then we are going 35 degrees North of West.
Hope that helps. If so, a positive feedback would be appreciated.
QUOTE (meBigGuy+Feb 8 2008, 10:31 AM)
Hope that helps. If so, a positive feedback would be appreciated.
linkhero can't post feedback yet either mbg
linkhero can't post feedback yet either mbg
QUOTE (linkhero1+Feb 6 2008, 03:13 PM)
3.While exploring a cave, a spelunker starts at the entrance and moves the following distances. She goes 75 m north, 250 m east, 135 m at an angle 30° north of east, and 125 m south. Find the resultant displacement from the cave entrance.
Magnitude
It has been years since I was in any math class, but I tend to rely on visualization for things like these. Try to picture in your mind some familiar landscape, somewhere where the directions north, south, east, west feel familiar. Now imagine a cave in that area. See yourself go in. Presumably the mouth of the cave faces north. I walk straight in a short way then turn right and walk a bit longer. I veer slightly northward, then take a very abrupt turn south. It is dark, and I am beginning to get nervous. I get a flashlight and draw the lines retracing my steps on paper. Is there a way out? Am I dead? Is my sense of direction working?
QUOTE (bm1957+Feb 8 2008, 01:43 PM)
LOL sorry for not coming back. The forum seemed dead so I actually figured out how to do them, and I feel stupid for not knowing how to do them. I have a new problem, which may seem easy to you guys but I'm not that good with physics.
I can't give feedback because, well I'm a newb.
I can't give feedback because, well I'm a newb.
QUOTE (linkhero1+Feb 6 2008, 07:13 PM)
1. An airplane flies 210 km due west from city A to city B and then 312 km in the direction of 35.0° north of west from city B to city C.
West = (-1,0) direction
35.0° North of West = (-cos 35.0°, sin 35.0°) direction = (-.819152, .573576)
A->B = 210 km × (-1,0) = (-210 km, 0 km)
B->C = 312 km × (-cos 35.0°, sin 35.0°) = (-256 km, 179 km)
A->C = (-210 km, 0 km) + (-256 km, 179 km) = (-466 km, 179 km)
magnitude of A->C = 499 km
West = (-1,0) direction
35.0° North of West = (-cos 35.0°, sin 35.0°) direction = (-.819152, .573576)
A->B = 210 km × (-1,0) = (-210 km, 0 km)
B->C = 312 km × (-cos 35.0°, sin 35.0°) = (-256 km, 179 km)
A->C = (-210 km, 0 km) + (-256 km, 179 km) = (-466 km, 179 km)
magnitude of A->C = 499 km
QUOTE (linkhero1+Feb 6 2008, 07:13 PM)
2. Fox Mulder is trapped in a maze. To find his way out, he walks 10.0 m, makes a 90.0° right turn, walks 5.00 m, makes another 90.0° right turn, and walks 6.50 m. What is his displacement from his initial position?
A->B = (0 m,10.0 m)
B->C = (5.00 m, 0 m)
C->D = (0 m, 6.50 m)
A->D = (0 m,10.0 m) + (5.00 m, 0 m) + (0 m, 6.50 m) = (5.00 m, 3.50 m)
magnitude A->D = 6.10 m
A->B = (0 m,10.0 m)
B->C = (5.00 m, 0 m)
C->D = (0 m, 6.50 m)
A->D = (0 m,10.0 m) + (5.00 m, 0 m) + (0 m, 6.50 m) = (5.00 m, 3.50 m)
magnitude A->D = 6.10 m
QUOTE (linkhero1+Feb 6 2008, 07:13 PM)
3.While exploring a cave, a spelunker starts at the entrance and moves the following distances. She goes 75 m north, 250 m east, 135 m at an angle 30° north of east, and 125 m south. Find the resultant displacement from the cave entrance.
Magnitude
A->E = 75 m × (0, 1) + 250 m × (1, 0) + 135 m × (cos 30°, sin 30°) + 125 m × (0, -1)
= 75 m × (0, 1) + 250 m × (1, 0) + 135 m × (.866, 0.500) + 125 m × (0, -1)
= (0 m, 75 m) + (250 m, 0 m) + (117 m, 67.5 m) + (0 m, -125 m)
= (367 m, 17.5 m)
magnitude A->E = 367 m (because it's less than 367.5 m)
Magnitude
A->E = 75 m × (0, 1) + 250 m × (1, 0) + 135 m × (cos 30°, sin 30°) + 125 m × (0, -1)
= 75 m × (0, 1) + 250 m × (1, 0) + 135 m × (.866, 0.500) + 125 m × (0, -1)
= (0 m, 75 m) + (250 m, 0 m) + (117 m, 67.5 m) + (0 m, -125 m)
= (367 m, 17.5 m)
magnitude A->E = 367 m (because it's less than 367.5 m)
QUOTE (linkhero1+Feb 14 2008, 07:19 PM)
LOL sorry for not coming back. The forum seemed dead so I actually figured out how to do them, and I feel stupid for not knowing how to do them. I have a new problem, which may seem easy to you guys but I'm not that good with physics.
I can't give feedback because, well I'm a newb.
People get around to answering eventually. It is hoped that you will get better at figuring it out. I wish you well.
Don't get lost in any caves.....
I can't give feedback because, well I'm a newb.
People get around to answering eventually. It is hoped that you will get better at figuring it out. I wish you well.
Don't get lost in any caves.....
QUOTE (linkhero1+Feb 14 2008, 11:19 PM)
LOL sorry for not coming back. The forum seemed dead so I actually figured out how to do them, and I feel stupid for not knowing how to do them. I have a new problem, which may seem easy to you guys but I'm not that good with physics.
I can't give feedback because, well I'm a newb.
...and you shouldn't give it because people beg you for positive feedback just to pad their score. Especially, when they give you incomplete solutions.....
I can't give feedback because, well I'm a newb.
...and you shouldn't give it because people beg you for positive feedback just to pad their score. Especially, when they give you incomplete solutions.....
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