Results 1 to 4 of 4

Math Help - bearings

  1. #1
    Newbie
    Joined
    Jun 2008
    Posts
    5

    bearings

    An overhead power cable 8000 metres miles long travels due north. Another cable starts from the south end of this in a direction N. 24 E. A third cable starts from the north end of the first one and travels in a direction S. 54 E. Find the length of this cable if it travels in a straight line to meet the second cable, and find the distance of the junction
    from the line of the first cable.

    thanks
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    earboth's Avatar
    Joined
    Jan 2006
    From
    Germany
    Posts
    5,830
    Thanks
    123
    Quote Originally Posted by Steven H View Post
    An overhead power cable 8000 metres miles long travels due north. Another cable starts from the south end of this in a direction N. 24 E. A third cable starts from the north end of the first one and travels in a direction S. 54 E. Find the length of this cable if it travels in a straight line to meet the second cable, and find the distance of the junction
    from the line of the first cable.

    thanks
    1. Draw a sketch

    2. Calculate the value of angle \gamma

    3. Use Sine Rule to calculate the distances x and s:

    \frac x{8000} = \frac{\sin(24^\circ)}{\sin(\gamma)} Solve for x.

    \frac s{8000} = \frac{\sin(54^\circ)}{\sin(\gamma)} Solve for s.
    Attached Thumbnails Attached Thumbnails bearings-threecables.gif  
    Follow Math Help Forum on Facebook and Google+

  3. #3
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    Quote Originally Posted by Steven H View Post
    An overhead power cable 8000 metres miles long travels due north. Another cable starts from the south end of this in a direction N. 24 E. A third cable starts from the north end of the first one and travels in a direction S. 54 E. Find the length of this cable if it travels in a straight line to meet the second cable, and find the distance of the junction

    from the line of the first cable.

    thanks
    A drawing would be nice. I'm confused about your direction of the third cable from the North. To travel SE, wouldn't the degrees be between 90 and 180, unless you mean 54 degrees south of east. In which case the direction would be 144 degees (90+54). Otherwise 54 degrees is NE. Maybe it's just me.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Jun 2008
    Posts
    5
    Quote Originally Posted by masters View Post
    A drawing would be nice. I'm confused about your direction of the third cable from the North. To travel SE, wouldn't the degrees be between 90 and 180, unless you mean 54 degrees south of east. In which case the direction would be 144 degees (90+54). Otherwise 54 degrees is NE. Maybe it's just me.

    the cable is traveling in a south east direction, i think this should help, i got this from the part where is staes that the third cable starts at the north end on the first one.

    thanks
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. bearings
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: August 3rd 2008, 08:31 PM
  2. Bearings Help
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: March 22nd 2008, 07:54 AM
  3. bearings
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: October 17th 2007, 09:04 PM
  4. bearings.. help
    Posted in the Trigonometry Forum
    Replies: 6
    Last Post: October 16th 2007, 03:41 PM
  5. bearings
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: October 14th 2007, 01:49 PM

Search Tags


/mathhelpforum @mathhelpforum