FORESTRY
GENERAL FORESTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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When using the topographic scale on an abney level at a distance of 66 feet and the readings are-4 to the base to the top of a tree, the total height is ____ ?
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49 feet
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41 feet
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82 feet
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98 feet
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Explanation:
Detailed explanation-1: -When used correctly, the Abney Level has an accuracy of about +/-0.5 m for a 20 m tall tree (ie about 2.5%). Measure the horizontal distance from the base of a vertical tree (or the position directly beneath the tree tip of a leaning tree) to a location where the required point on the tree (e.g. tree tip) can be seen.
Detailed explanation-2: -The vernier is of the extended type having the least count of 5′ or 10′. If the instrument is to be used as a hand level, the vernier is set to read zero on the graduated arc and the level is then used as an ordinary hand level.
There is 1 question to complete.