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Question
A window washer attempts to lean a ladder against a frictionless wall. He finds that the ladder slips on the ground when it is placed at an angle of less than 75°to the ground but remains in place when the angle is greater than 75°. The coefficient of static friction between the ladder and the ground:
A) is 0.13
B) is 0.27
C) is 1.3
D) depends on the mass of the ladder
E) depends on the length of the ladder
Answer
This answer is hidden. It contains 1 characters.
Related questions
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Q:
In a photoelectric effect experiment at a frequency above cut off, the stopping potential is proportional to:
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Q:
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Q:
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Q:
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5) decrease the separation between the slits
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Q:
The resolving power of a telescope can be increased by:
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Q:
Light of wavelength 480 nm falls on a slit of width 3.5 m. What is the relative intensity (that is, the value of I/Im) of the diffraction pattern at an angle of 18?
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Q:
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