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Minor Versionm

by Vishal Bhatt

Introduction

Make your own sextant using a plastic straw, thread and some weight. Use it to measure the angle of elevation to different objects around you.

  1. Take a sheet of paper . Place a protractor on it . Start marking points from 90 degree .
    • Take a sheet of paper .

    • Place a protractor on it .

    • Start marking points from 90 degree .

  2. Mark each point up to 0 degree .  Join all the points . Extend each point by 5 cm , using a ruler. Mark two points 1 cm away from the point of origin on the 0 degree as well as 90 degree line.
    • Mark each point up to 0 degree . Join all the points .

    • Extend each point by 5 cm , using a ruler.

    • Mark two points 1 cm away from the point of origin on the 0 degree as well as 90 degree line.

  3. Join all the points and extend to get a 1 cm margin as shown in figure. Cut the shape to get half protractor on paper. Cut the shape to get half protractor on paper.
    • Join all the points and extend to get a 1 cm margin as shown in figure.

    • Cut the shape to get half protractor on paper.

  4. Take a cardboard sheet . Stick the half protractor on cardboard using fevicol . Cut the extra cardboard, using scissors .
    • Take a cardboard sheet .

    • Stick the half protractor on cardboard using fevicol .

    • Cut the extra cardboard, using scissors .

  5. Make a hole in the center , where all points meat , using scissors . Take a 20 cm thread . Take a 20 cm thread .
    • Make a hole in the center , where all points meat , using scissors .

    • Take a 20 cm thread .

  6. Insert the thread through the hole. Knot the thread so that it does not slip back through the hole. On the other side of thread, tie some weight like a ring magnet.
    • Insert the thread through the hole.

    • Knot the thread so that it does not slip back through the hole.

    • On the other side of thread, tie some weight like a ring magnet.

    • The weight needs to be heavy enough to keep the thread taught.

  7. Take a 20 cm straw . Fix straw with tape on one edge of the protractor, as shown . Darken the lines using pen or sketch pen and write down the degrees. Using eraser, erase all the lines marked with pencil.
    • Take a 20 cm straw .

    • Fix straw with tape on one edge of the protractor, as shown .

    • Darken the lines using pen or sketch pen and write down the degrees. Using eraser, erase all the lines marked with pencil.

  8. Look at any object around through the straw and measure the angle of elevation to that point.
    • Look at any object around through the straw and measure the angle of elevation to that point.

  9. Identify any 5 indoor objects and measure as well as record the angle of elevation/depression in standing and sitting position. Repeat the above for any 5 outdoor objects which are at least 100 metres away from you.
    • Identify any 5 indoor objects and measure as well as record the angle of elevation/depression in standing and sitting position.

    • Repeat the above for any 5 outdoor objects which are at least 100 metres away from you.

Finish Line

Vishal Bhatt

Member since: 04/26/2017

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78 Guides authored

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