science midterm

Question 1

what is a gnomon and what does it show

Answer 1

the projecting piece on a sundial that shows the time by the position of its shadow

Question 2

what is the Coriolis effect and what does it show

Answer 2

the winds move slightly to the right in the northern hemisphere and slightly to the left in the Southern Hemisphere. this shows wind patterns and possible storms

Question 3

during the process of condensation, how much energy is gained or released

Answer 3

2260 j/g of heat energy is released

Question 4

how is the nearness to a sea-floor spreading center indicate the age of seafloor rock and sediments

Answer 4

the closer the rock and sediments are to the seafloor spreading center, the newer they are. When they are far away from the center, they are very old

Question 5

in which portion if the electromagnetic spectrum is the maximum intensity

Answer 5

infrared

Question 6

how to calculate origin time

Answer 6

p-wave travel time minus p-wave arrival time

Question 7

what happens to rocks that are carried far away from their origin by a river?what is the name of this weathering

Answer 7

they get deposited. erosion

Question 8

what are some monominerlic rocks

Answer 8

marble quartzite

Question 9

difference between continental and oceanic crust

Answer 9

continental- granite, low density, thick

oceanic- basalt, high density, thin

Question 10

determine the relative rate of p-waves and s-waves through the layers of the earth with different densities

Answer 10

p-waves move faster than s-waves. p-waves travel through solids and liquids, so they can travel all the way through the earth. s-waves however can’t travel through liquid, so they bounce off the outer core which is liquid rock.

Question 11

the Hawaiian islands formed from

Answer 11

a hot spot

Question 12

what is chemical fractionation and what causes it

Answer 12

density stratification. it is caused by differences in density

Question 13

when did earth and other planets begin chemical fractionation

Answer 13

4.6 billion years ago

Question 14

how many Half-lives have passed if a sample contains 12.5% of its original carbon-14

Answer 14

3

Question 15

why is there a greater distance between the p-wave and the s-wave arrival times a seismic stations farther from the epicenter than closer to the epicenter of an earthquake

Answer 15

the greater the distance the greater the gap

Question 16

what is a shadow zone and why do they form

Answer 16

locations on earths surface where no body waves from a particular earthquake can be detected. shadow zones form because the materials that make up earths interior are not uniform in rigidity

Question 17

why can andesite and diorite both have the same percentage of mineral composition by volume and yet be two different igneous rocks

Answer 17

andesite- external, large grain size

diorite-internal, small grain size