In which region of the Earth is heat transfer mainly by conduction? (A) mantle;
ID: 2075296 • Letter: I
Question
In which region of the Earth is heat transfer mainly by conduction? (A) mantle; (B) inner core; (C) outer core; (D) none of them. It is believed that the source of Earth's magnetic field lies in the (A) crust; (B) mantle; (C) inner core; (D) outer core; (E) electromagnetic radiation from the Sun. Spring tides occur: (A) during a full or a new moon; (B) when the moon is in the first and third quarter of the month; (C) mostly in Spring; (D) when the moon is closest to Earth (at its perigee); (E) when the gravitational forces of the Moon and the Sun are perpendicular to one another. If there are two tides around the Earth at any instant, explain why the interval between successive high tides is 12 hours 25 minutes rather than 12 hours. ______Explanation / Answer
3) The core of the Earth is very hot. The thermal energy of that core is transferred to the surface of the Earth and lower levels of the oceans by conduction. So the answer is ( D ) Outer core.
4) Right at the heart of the Earth is a solid inner core, two thirds of the size of the Moon and composed primarily of iron. At a hellish 5,700°C, this iron is as hot as the Sun’s surface, but the crushing pressure caused by gravity prevents it from becoming liquid. So the answer is (C) inner core.
6)
5) Tides are created because the Earth and the moon are attracted to each other, just like magnets are attracted to each other. The moon tries to pull at anything on the Earth to bring it closer. But, the Earth is able to hold onto everything except the water. Since the water is always moving, the Earth cannot hold onto it, and the moon is able to pull at it. Each day, there are two high tides and two low tides. The ocean is constantly moving from high tide to low tide, and then back to high tide. Tides are the periodic rise and falling of large bodies of water. Winds and currents move the surface water causing waves. The gravitational attraction of the moon causes the oceans to bulge out in the direction of the moon.
So answer is ( D) when moon is closest to the earth.
6)In the semidiurnal tide, there are two high and two low waters each tidal day, with relatively small differences in the respective highs and lows Tides.
Since the lunar tide-producing force has the greatest effect in producing tides at most places, the tides “follow the Moon.” Because the Earth rotates, high water lags behind both upper and lower meridian passage of the Moon. The tidal day, which is also the lunar day, is the time between consecutive transits of the Moon, or 24 hours and 50 minutes on the average. Where the tide is largely semidiurnal in type, the lunitidal interval (the interval between the Moon’s meridian transit and a particular phase of tide) is fairly constant throughout the month, varying somewhat with the tidal cycles. There are many places, however, where solar or diurnal oscillations are effective in upsetting this relationship. The interval generally given is the average elapsed time from the meridian transit (upper or lower) of the Moon until the next high tide. This may be called mean high water lunitidal interval or corrected(or mean) establishment.