A small source radiates an electromagnetic wave with a single frequency into vacuum, equally in all directions. As the wave moves, the amplitude of its electric field:
1.increases.
2.decreases.
3.stays constant.
2
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Double-Slit Interference: A double-slit experiment uses coherent light of wavelength 633 nm with a slit separation of 0.100 mm and a screen placed 2.0 m away.(a) How wide on the screen is the central bright fringe?(b) What is the distance on the screen between first-order and second-order bright fringes?(c) What is the angular separation (in radians) between the central maximum and the first-order maximum?
What will be an ideal response?
A spring is stretched 10 cm by a suspended 1-kg block. If two such springs side-by-side are used to suspend the 1-kg block, each spring will then stretch
A) 5 cm. B) 10 cm. C) 20 cm. D) 30 cm. E) none of the above
A crane lifts a steel submarine of density 7800 kg/m3 and mass 20,000 kg. What is the tension in the lifting cable (a) when the submarine is submerged in water of density 1000 kg/m3, and (b) when it is entirely out of the water?
A) (a) 2.0 × 105 N (b) 1.7 × 105 N B) (a) 1.7 × 105 N (b) 2.0 × 105 N C) (a) 2.6 × 103 N (b) 2.0 × 105 N D) (a) 2.0 × 105 N (b) 2.6 × 103 N
Twenty milliseconds is
a. 0.00002 s b. 0.0002 s c. 0.002 s d. 0.02 s e. 20000 s