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Question
Two vectors lie with their tails at the same point. When the angle between them is increased by 20ï‚°their scalar product has the same magnitude but changes from positive to negative. The original angle between them was:
A) 0
B) 60°
C) 70°
D) 80°
E) 90°
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:
In a photoelectric effect experiment at a frequency above cut off, the number of electrons ejected is proportional to:
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Q:
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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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