Aplano-convex glass lens of radius of curvature 1.8 m rests on an optically flat glass plate. the arrangement is illuminated from above with monochromatic light of 559-nm wavelength. the indexes of refraction of the lens and plate are 1.6. determine the radii of the first and second bright fringes in the reflected light.

After the near spacecraft passed mathilde, on several occasions rocket propellant was expelled to adjust the spacecraft's momentum in order to follow a path that would approach the asteroid eros, the final destination for the mission. after getting close to eros, further small adjustments made the momentum just right to give a circular orbit of radius 45 km (45 × 10^3 m) around the asteroid. so much propellant had been used that the final mass of the spacecraft while in circular orbit around eros was only 545 kg. the spacecraft took 1.04 days to make one complete circular orbit around eros. calculate what the mass of eros must be.

What will a positive and a negative charge do if they are separated from each other?

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