A distance R away from a light source we observe which of the following for the electromagnetic field it produces?
A) Both the light intensity and the magnitude of the electric field drop as 1/R2.
B) The light intensity drops as 1/R2, but the magnitude of the electric field drops as 1/R.
C) Both the light intensity and the magnitude of the electric field drop as 1/R.
D) The light intensity drops as 1/R, but the magnitude of the electric field drops as 1/R2.
E) None of the previous answers is correct.
B
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A spring (k = 600 N/m) is placed in a vertical position with its lower end supported by a horizontal surface. The upper end is depressed 20 cm, and a 4.0-kg block is placed on top of the depressed spring. The system is then released from rest. How far above the point of release will the block rise?
a. 46 cm b. 36 cm c. 41 cm d. 31 cm e. 20 cm
A projectile is projected from the origin with a velocity of 45.0 m/s at an angle of 30.0 degrees above the horizontal. What is the range of the projectile?
A. 92.0 m B. 105 m C. 134 m D. 179m E. 205 m
A dam is thicker at the bottom than at the top mainly because
A) water is denser at deeper levels. B) water pressure increases with depth. C) surface tension exists only on the surface of liquids. D) it looks better. E) none of the above
If you looked at the field of view seen in this Hubble Space telescope with your naked eye, about how big would it appear in the sky?
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