Стр.138-139 Across the curriculum ГДЗ Комарова Ларионова 9 класс

Приведем выдержку из задания из учебника Комарова, Ларионова 9 класс, Русское слово: 5 Science
High tides and low tides
1 Look at the photos and decide which one shows a high tide and which one shows a low tide.
2 Read the text and say which of the diagrams represents:
a) when very high tides occur
b) when very low tides occur
Gravity and its effects on the tides
The Earth orbits the Sun approximately every 365 days and the Moon orbits the Earth approximately every 27 days. It is gravity which keeps the Earth and Moon in their orbits, but gravity is also what affects the tides.
Although the Sun’s gravity is much stronger than the gravitational force of the Moon, in fact, it is the Moon which has the greater effect on the Earth’s tides because it is nearer to the Earth. But both the Sun and Moon affect the tides.
Water in the oceans on Earth is ‘pulled’ into different tide patterns by gravity.
When the gravity of the Moon and Sun are on the same axis, there will be high tides (diagrams 1 and 3). When the Moon and Sun are perpendicular, the tides are very low (diagram 2).
Analysis of ocean movements and tides is very complex because oceans vary in depth and shape and every coastline around the world is unique. This means that some places have two tides a day and some only one, while other places have no visible tide at all.
When bad weather and storms combine with high tides, flooding often takes place.
3 Read the text again and answer the questions.
1 What is the Moon’s orbit of the Earth?
2 Does the Sun’s gravity affect the Earth’s tides?
3 What other factors affect the tides?
4 What combination might result in flooding?
Sir Isaac Newton
4 Read the text and put the paragraphs in the correct order.
One of the world’s greatest scientists
a Newton is famous as the man who realized that gravity was at work when he was hit on the head by an apple falling from a tree. This story may be a legend, but in 1687 he published Philosophiae Naturalis Principia Malhematica (Mathematical Principles of Natural Philosophy’) which showed that gravity is a universal force.
b Sir Isaac Newton was one of the greatest scientists of all time. He was born in 1643 and he studied at Cambridge University, where he later became professor of mathematics.
c He was also famous for his bad temper and eccentricities in later life, but he made many other important contributions to science before his death in 1727.
d His interests were very wide and from the mid 1660s he studied not only mathematics, but also physics and astronomy. He studied the composition of light and colours and he developed a powerful telescope to study the stars.
Newton’s three laws of motion
5 Match the sentence halves to make Newton’s Laws.
1 Newton’s first law
An object in a state of uniform motion
2 Newton’s second law
Force =
3 Newton’s third law
For every action
a) there is an equal and opposite reaction.
b) remains in motion unless acted on by an external force.
c) mass x acceleration
Project
You are going to find out more about gravity.
Plan
Find out how satellites are put into orbit and why they do not float out into space.
Research
Find information about satellites. Look in the library or on the Internet.
Prepare
Draw some diagrams and write a text to explain your findings.
Present your material
Present your completed project to your classmates and teacher.
*Цитирирование части задания со ссылкой на учебник производится исключительно в учебных целях для лучшего понимания разбора решения задания.

Ответ

1. The photo with the higher water level shows a high tide, and the photo with the lower water level shows a low tide.

2.
a) very high tides occur when the Moon and the Sun are on the same axis — diagrams 1 and 3;
b) very low tides occur when the Moon and the Sun are perpendicular — diagram 2.

3.

1. The Moon orbits the Earth approximately every 27 days.
2. Yes, it does.
3. Oceans vary in depth and shape, and every coastline is unique.
4. Bad weather and storms combined with high tides might result in flooding.

4. b, d, a, c

5.

• Newton’s first law — b An object in a state of uniform motion remains in motion unless acted on by an external force.
• Newton’s second law — c Force = mass × acceleration.
• Newton’s third law — a For every action there is an equal and opposite reaction.