tenth paper

Question 1

hot objects emit radiation over a wide range of _____

Answer 1

wavelengths (hot burner)

Question 2

room temperature objects emit radiation that is mostly _____

Answer 2

infrared (mammals)

Question 3

objects hotter than 1000 degrees begin to emit ____ ____

Answer 3

visible light (sun)

Question 4

what is the law of reflection?

Answer 4

the angle of incidence is always equal to the angle of reflection, when a light ray encounters a reflective surface, the angles are always measured relative to the normal line.

Question 5

give an example of scattering

Answer 5

the sky is blue because in the earths atmosphere blue light is scattered the most

Question 6

define defraction

Answer 6

the bending of light around objects into what would otherwise be a shadowed region

Question 7

when does defraction occur?

Answer 7

when light passes through a very small opening or by a sharp edge

Question 8

define interference

Answer 8

pattern of bright lines and dark zones when light from a single source passes through slits

Question 9

define constructive interference

Answer 9

the light from each slit constructively interferes

Question 10

define destructive interference

Answer 10

the light from each slit destructively interferes

Question 11

define refraction

Answer 11

part of the ray passes into the glass while the rest reflects

Question 12

what is the law of refraction?

Answer 12

a light ray is bent towards the normal when it enters a transparent medium in which light travels slower.
A light ray is bent away from the normal when it enters a transparent medium in which light travels faster

Question 13

define total internal refraction

Answer 13

for light going from a more dense to less dense medium, there is a critical angle of incidence, the light does not go through the boundary, but is reflected back into the more dense medium

Question 14

define dispersion

Answer 14

a phenomenon in which the speed of light through a medium depends on the frequency of the light

Question 15

what is the photoelectric effect

Answer 15

A beam of light knocks electrons loose from a substance to produce a flow of electricity.

Question 16

what do you need to produce the photoelectric effect?

Answer 16

light that behaves like tiny particles

Question 17

define photons

Answer 17

tiny particles of light that travel at 300,000 km/h

Question 18

what does the amount of energy carried by photons depend on?

Answer 18

the wavelength of the EM radiation

Question 19

define light as a particle

Answer 19

light is a form of energy and it gives off its energy to matter when its absorbed