Science Test-energy

Question 0

What would happen if we didn’t have the natural greenhouse effect?

Answer 0

Our earth would have temperatures similar to the moon and we would not be able to live here. Far too hot by day and far too cold by night. The natural greenhouse effect has enable life to evolve.

Question 1

What is the greenhouse effect?

Answer 1

A process where some of the infrared radiation emitted by the Earth’s surface is trapped by greenhouse gases, which helps moderate the temperatures at the earths surface.

Question 2

What is the average temperature on the moon and the earth?

Answer 2

The moon- -17 degrees

The earth- 16 degrees

Question 3

Cycles of greenhouse gases?

Answer 3

Natural cycles ensure that the proportion of the greenhouse gases in the atmosphere remain steady. These cycles consist of natural processes in which they are released into the air and other natural processes in which they are removed from the air.

Question 4

What is cellular respiration?

Answer 4

One of the natural processes in which carbon dioxide is released into the air. The chemical reaction worded equation is:
Glucose+ oxygen-> carbon dioxide + water+ energy (ATP)
This reaction occurs in every cell within all those living organisms to obtain the energy they need to survive.

Question 5

Natural process that removes carbon dioxide from the air?

Answer 5

Photosynthesis is a chemical reaction in which plants and other certain organisms absorb carbon dioxide from the air and water from the ground to produce glucose.
carbon dioxide+water+energy(ATP)->glucose + energy

Question 6

What is the enhanced greenhouse effect?

Answer 6

Is the trapping of additional infrared radiation by the excessive amounts of greenhouse gases in the atmosphere that have been produced as a result of human activity.

Question 7

Consequences from enhanced greenhouse gases?

Answer 7

Climate change- greater extremes of drought and heavy rainfall and an increase of the severity of cyclones, typhoons and other extreme weather events.
Melting of polar icecaps and glaciers- causing many species dependent on ice possibly endangered.
Change in weather patterns
Increase in temperature of the upper level of the oceans
Rising sea levels
Spread of tropical diseases- such as malaria
Spread of invasive species
Not enough balance due to human activity.

Question 8

What causes the enhanced greenhouse effect?

Answer 8

The human activity such as the burning of coal, natural gases and oil, mass production of steel, cement of aluminium, huge piles of rotting garbage, burning trees, methane produced from cattle etc.

Question 9

What can be done to help global warming?

Answer 9

Humans need to be smarter about sustainable living to reduce greenhouse gas emissions.
E.g 
using energy saving light bulbs
Heat and cool efficiently
Insulate houses
Recycle
Etc

Question 10

What is the law of conservation of energy?

Answer 10

The law of conservation of energy says that energy cannot be created or destroyed. It simply changes from one type to another. Each conversion also involves waste of energy ( energy you don’t want to produce and can’t be used) commonly heat energy.
E.g your mobile phone is meant to convert chemical potential energy into electricity, but at the same time creates heat energy.

Question 11

Units of energy

Answer 11

J- joules

Question 12

Types of energy?

Answer 12

Kinetic, electrical, gravitational potential, elastic potential, heat, light, sound, chemical, nuclear, mechanical.

Question 13

What is kinetic energy?

Answer 13

Is energy that can be seen doing things. The main types of kinetic energy are:
Mechanical energy- energy of moving parts
Light energy- energy that warms the planet, burns our skin and allows us to see things more easily.
Heat energy- energy to keep us warm
Sound energy- energy that we can hear due to objects vibrating
Electrical energy- energy used to make all our electrical appliances work. It pushes an electrical current through a wire.

Question 14

What is potential energy?

Answer 14

Also called stored energy. The. Ain types are:
Gravitational potential energy- energy stored due to an objects height above earth. It changes to kinetic energy as the object falls.
Chemical potential energy-energy that is stored inside chemicals that often produce heat and light when burnt.
Elastic potential energy- energy stored inside springs and rubber bands when they are stretched or compressed.
Nuclear potential energy- energy stored inside atoms of elements such as uranium or hydrogen.

Question 15

What is energy transfer?

Answer 15

When energy has moved from one object to another.

E.g when cooking, heat energy from the stove is transferred to the saucepan and then to the food inside.

Question 16

What is energy transformation?

Answer 16

When one type of energy is transformed into another type.
E.g
Chemical potential energy->electrical energy->light and heat energy

Question 17

What is non renewable energy?

Answer 17

Non renewable energy are resources that cannot be replaced to an equal level of consumption. For example fossil fuels.

Question 18

What are fossil fuels?

Answer 18

They are fuels such as coal, oil and natural gas. They are produced from ancient organisms, mainly plants, that lived millions of years ago.

Question 19

What is renewable energy?

Answer 19

It is energy from a source that is not depleted when used: 
E.g
Solar
Wind
Tidal
Hydro
Geothermal 
Wave
Biogas
Fossil fuels
Nuclear

Question 20

What does too many fossil fuels cause?

Answer 20

The burning of fossil fuels for electricity results in the production of greenhouse gases. Too many of these greenhouse gases in our atmosphere will cause global warming, and as a result a domino effect of a changed earth in our atmosphere.

Question 21

How do you work out the calculation of power?

Answer 21

P=V><L
P= power in milliwatts (mW)
V= voltage in volts(V)
I= current in milliamps (mA)

Question 22

How do wind turbines work?

Answer 22

Wind turbines transform the kinetic energy of the wind into mechanical energy of the turbine, and then the generator transforms it into electricity.
Kinetic energy-> mechanical energy->electricity

Question 23

Disadvantages and advantages of wind turbines?

Answer 23

Advantages:

• renewable source
• do not emit greenhouse gases
• more energy efficient than most power stations that burn fossil fuels
• cheaper to run than many other energy sources
• can be established in remote areas

Disadvantages

• electrical power relies on wind speed and direction
• can be damaged by strong winds
• can be corroded by salt in the air rear ocean
• some people think they spoil landscape and that the noise is annoying.

Question 24

What are solar panels?

Answer 24

Solar panels consist of a set of solar cells. These cells, Aka photovoltaic cells convert the Suns energy directly into electricity. Solar panels can be connected in a group to form a solar array.
Solar energy-> electrical energy

Question 25

Disadvantages and advantages of solar panels?

Answer 25

Advantages:

• renewable resource
• do not emit greenhouse gases
• solar energy is free
• operate without noise
• can be used in remote areas
• also can create heated water.

Disadvantages

• expensive to install
• amount of power produced varies on sun exposure to panel
• greenhouse gases are produced in the shipping, making and installing of these panels.
• some people don’t like there appearance
• low energy efficiency(10-15%)

Question 26

Examples of greenhouse gases

Answer 26

Water vapour
Methane
Carbon dioxide 
Ozone
Nitrous dioxide