It is worth emphasising that the gravitational energy (or gravitational potential energy, to give it the full name) of an object increases when it moves in the opposite direction to the gravitational force (i.e. when it moves upwards). This relationship between energy and force does not apply only to gravity. For many forces, motion against the force (that is, in the opposite direction to the force) allows energy to be stored, and this energy can be reclaimed when the obj
Author(s): The Open University

Female guppies begin to breed as soon as they become mature at about three months old; they then produce clutches of eggs, most of which become fertilized, at roughly one-month intervals until they die or become too old. Clutches vary in size from one to 40 eggs; the average clutch contains about 10 eggs. Thus, female guppies produce a large number of offspring during their lives, far more than can survive to maturity.

Author(s): The Open University

In our last example, we consider a pentagon with two pairs of edges identified. As we saw in Section 2.3, identification of the edges produces a torus with a hole. In this case there are five vertex-neighbourhoods to fit together, as shown in Author(s): The Open University

We check that Tf satisfies conditions (T1)–(T3) for a topology.

Since (T1)–(T3) are satisfied, Tf is a topology on I(X).

Thus (I(X),Tf) is a topological space. We give the topology Tf a sp
Author(s): The Open University

Subdivisions of surfaces lead to the third number used to classify surfaces, the Euler characteristic.

Definition

The Euler characteristic χ of a subdivision of a surface is

Author(s): The Open University

We now consider one of the most important non-orientable surfaces – the projective plane (sometimes called the real projective plane). In Section 2 we introduced it as the surface obtained from a rectangle by identifying each pair of opposite edges in opposite directions, as shown in
Author(s): The Open University

Studying mammals: The opportunists
Many mammals are food specialists, with complex adaptations that gear them toward a particular food source. So how do the omnivores survive and prosper without these fancy evolutionary features? This unit examines the physiology, diet and strategies of some of these opportunistic feeders. It is the sixth unit in the ‘Studying mammals’ series. Fir
Author(s): Creator not set

Animals at the extremes: The desert environment
Animal life has adapted to survive in the most unlikely and inhospitable habitats. This unit looks at the surprisingly diverse desert climates throughout the world and mammals, birds, lizards and amphibians that survive there. It splits these animals into three groups according to their strategy for survival: evaders, evaporators and endurers, then discusses how these strategies work on a biochemical and physiological level.Author(s): Creator not set

Understanding the environment: Flows and feedback
There is increasing recognition that the reductionist mindset that is currently dominating society, rooted in unlimited economic growth unperceptive to its social and environmental impact, cannot resolve the converging environmental, social and economic crises we now face. The primary aim of this unit is to encourage the shift away from reductionist and human centred thinking towards a holistic and ecological worldview.Author(s): Creator not set

Understanding the environment: Complexity and chaos
There is increasing recognition that the reductionist mindset that is currently dominating society, rooted in unlimited economic growth unperceptive to its social and environmental impact, cannot resolve the converging environmental, social and economic crises we now face. The primary aim of this unit is to encourage the shift away from reductionist and human centred thinking towards a holistic and ecological worldview.Author(s): Creator not set

Timeline of The Space Race - Wiki Article
The Space Race was an informal competition between the United States and the Soviet Union that lasted roughly from 1957 to 1975. (01:20)
Author(s): No creator set

Lesson 01 - One Minute Luxembourgish
In lesson 01 of One Minute Luxembourgish you will learn how to say 'hello' and 'goodbye' in Luxembourgish. Remember - even a few phrases of a language can help you make friends and enjoy travel more. Find out more about One Minute Languages at our website - http://www.oneminutelanguages.com. One Minute Luxembourgish is brought to you by the Radio Lingua Network and is ©Copyright 2008.Author(s): No creator set

The Team and References

Author(s): No creator set

Daljinsko učenje - modeli, tehnološki uticaj i razvoj daljisnki orjetisanih sredina

Author(s): No creator set

Three Anti-Social Skills to Improve Your Writing
You need social skills to have a conversation in real life -- but they're quite different from the skills you need to write good dialogue. Educator Nadia Kalman suggests a few "anti-social skills," like eavesdropping and muttering to yourself, that can help you write an effective dialogue for your next story.  (03:46)

Author(s): No creator set

The Chancellor's Corner
The Ohio Department of Health completed Thursday its final site visit to UTMC on behalf of the Centers for Medicare & Medicaid Services and the team said in an exit interview they will recommend the hospital meets all conditions.
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Er zijn verschillende tabbladen waarin je natuurlijke getallen kan afronden van op het tiental tot op het miljoen.

Als je het antwoord juist hebt, krijgt de cel een groene kleur.

je kan de werkbladen ook …

Author(s): No creator set

Brian Beckman interviews JavaScript/CoffeeScript developer who's written an excellent CoffeeScript compiler, Michael Ficarra. If you're curious about CoffeeScript, then this is for you ( no demos or code, though; just technical conversation done the Beckman way ) Tune in!

Cast:

B
Author(s): Charles

Arithmetic, Population, and Energy Part 5 of 8

This part of the lecture discusses an outrageously incorrect statement in Time Magazine about how long coal resources could last, as well as other similarly incorrect statements in the media.