20點,物理(1),請列原因,

1.light is so fast:
a.its speed cannot be measured, so generally considered infinite
b.but speed of light is less than the speed of sound c.but we can still measure its speed d.none of the above
2.the nature of light can be explained by:
a.treating light as a ray traveling in a straight line b.treating light as a ray traveling in a circle
c.treating light as a ray traveling in an ellipse d.all of a, b, and c
3.The Law of Reflection of light says that:
a.when light falls on an object, it is always 100% reflected back b.the angle of incidence is equal to the angle of reflection
c.the angle of incidence is equal to the angle of refraction d.none of a, b or c
4.one of the most common applications is the use of mirror. The reflected image in a flat mirror:
a.is always exactly the same as the source object b.is exactly the same as the source object but "opposite-handed"
c.is smaller than the source object d.is larger than the source object
5.when light falls on a surface of a piece of glass:
a.some light will be relected away, but some will be refracted b.all light will be reflected away c.all light will be refracted
d.all light will be absorbed
.same amount of light falls on two objects of the same color and texture. One has a smooth surface and the other has a rough surface
a.the one with the smooth surface will be look brighter b.the one with the rough surface will be look brighter
c.both will look to have the same brightness d.none of a, b or c
7.explain, using a diagram, your answer in (6)
8.from the figure, w may conclude that
a.n1>n2 b.n1=n2 c.n1<n2 d.none of the above
figure Q8: incident ray, angle of incidence, refractive Index n1; angle of refraction, refracted ray, refractive Index n2
9.a drop of water is sitting on a sheet with squares on it. See figure Q9. The lines of square under the water seem moved. This is due to:
a.light reflection b.light refraction c.light diffraction d.light dispersion
figure Q9:黑白格子圖像, 在某格有一圓形