Experiment 3- Air track (repeated 5 times)
Average= 40 seconds
Energy input= gravitational potential energy.
Output= kinetic energy+ heat+ sound.
Useful= kinetic energy.
Wasted= heat+ sound.
Energy input = 0.1 x 9.81 x 0.24 = 23.544J
Energy input= Mass x Gravity x Height
Energy output = 0.5 x 0.1 x (2.22 ÷ 0.4)2 = 1.54J
Energy output= 0.5 x Mass x Velocity²=0.5 x Mass (distance ÷ Time)²
Useful energy output = 1.54J
Gravitational potential energy → Kinetic energy + Heat energy
Efficiency = 1.54 ÷ 23.544 = 1.17864424%
Efficiency= Energy output ÷ Energy input
In this experiment we used electricity and timed how long it took to lift 800g mass from the bottom of the floor to the top on string. We recorded the voltage, mass of crane, length of string, and time it took to travel from the bottom to the top of it.
Experiment 4- Crane (repeated 3 times)
Useful energy= gravitational potential energy.
Wasted= heat and sound.
Output= heat+ sound+ gravitational potential energy.
Energy input = 0.17 x 8.34 x 17 = 24J
Energy input= Current x Voltage x Time
Energy output = 0.8 x 9.81 x 1.45 = 11.38J
Electrical energy → Kinetic energy + Heat energy → Gravitational potential energy + Heat energy
Efficiency = 11.38 ÷ 24 x 100 = 47.42%
In this last experiment we poured 500ml of water and timed how fast it took to get to the bottom. In the second part we put the tap on slowly and held the pipe in the funnel and timed it making sure the voltmeter and ammeter are on.
Experiment 5- Water Wheel
Energy input= (() × 0.5) × 9.81× height (1m).
Energy output = 0.3× 10.5× 10= 31.5J
Gravitational potential energy → Kinetic energy + Heat energy → Electrical energy + Heat energy.
Efficiency = 31.5%
Many tasks that a cell must perform such as, movement and synthesis of macromolecules require energy. A large part of the cells activities are therefore devoted to obtaining energy from the environment and using that energy to drive energy- requiring reactions. During nuclear changes, either some mass is converted into energy or some energy is converted into mass. Which occurs is dependent upon the specifics of the individual reaction.
(Chemical→ kinetic+ heat)
Value for efficiency:
Bomb colorimeter – Technician experiment (P7)
A Bomb-Calorimeter is used to measure the heat created by a sample burned under an oxygen atmosphere in a closed vessel, which is surrounded by water under controlled conditions.
The different equipment is designed to do many different functions such as the reaction chamber is a strong vessel that can withstand the intense pressure of heated gases. The chamber is filled with mostly oxygen gas and the fuel. An electrical circuit is wired into the chamber in order to electrically ignite the contents in order to perform a student of the heat released upon combustion. The reaction chamber is surrounded by a jacket of water with a thermometer inserted. The heat released from the chamber warms the water-filled jacket, allowing a scientist to determine the quantity of energy released by the reaction. The way a bomb colorimeter is operated is by a reaction taking place in a sealed metal container which is placed in the water in an insulated container. The heat flow from the reaction crosses the walls of the sealed container to the water and the temperature difference of the water is measured. Then the analysis takes place as for a bomb colorimeter it is more complex because the metal parts must also be taken into account.
The most efficient out of all the experiments was experiment 4 because a small amount of electrical energy produced kinetic energy + heat energy which caused gravitational potential energy + more heat energy. The efficiency of experiment 4 was 3790 % which is a substantial amount compared to the other experiments. Maximum productivity was achieved with minimal energy wasted as the wasted energy output was -1107 J.
Coal is considerably very cheap. You burn the coals and use it to heat up things as a fire. It releases carbon dioxide so pollutes the environment.
Gas is expensive than coal but it is simple to do and it is cleaner to the environment. Wind is free, but it isn’t a dependable source as it isn’t windy all the time. Hydroelectric has the same advantages and disadvantages as wind..
Nuclear is complicated and expensive to use but it is very difficult to dispose of the toxic waste that occur after using it.
Generating Efficiency-Research method
There are many methods of energy production which relate to being the most efficient. Electric power plant efficiency η is defined as the ratio between the useful electricity output from the generating unit, in a specific time and the energy value of the energy source supplied to the unit in the same time period.
Much of the energy content of the available energy sources is wasted by the energy conversion and distribution processes. Taking electric lighting as an example, less than 1% of the energy consumed to provide the electricity is ultimately converted into light energy. The other 99% is wasted in the supply chain. Using conventional fossil fuelled generating plant, losses accumulate as follows:
- 10% of the energy content of the fuel is lost in combustion and only 90% of the calorific content is transferred to the steam.
- The steam turbine efficiency in converting the energy content of the steam into mechanical energy is limited to about 40%.
- The rotary electrical generator is very efficient by comparison. The conversion efficiency of a large machine can be as high as 98% or 99%.
- Transmission of the electrical energy over the distribution grid between the power station and the consumer results in a distribution loss of 10% mainly due to the resistance of the electrical cables.
- Further energy is lost due to the energy conversion efficiency of the end user's appliance. Incandescent lighting is particularly inefficient converting only 2% of the electrical energy into light.
Solar energy is the good energy (light or heat) that comes from the sun. Only a small amount of the sun’s energy strikes the Earth. Solar power systems, once they’re up and operational last for 15-30 years. In 2008 solar only provided .02% of the world’s energy, that number is growing every year.
Also, Wind energy is another form of energy which the wind is used to generate mechanical power or electricity. People have been using energy from the wind for hundreds of years to pump water or grind grain. Today, we use wind turbines to generate electricity. However, wind energy does not produce harmful greenhouse gases or waste products. According to the American Wind Energy Association, wind reduces emissions. One modern turbine could prevent 1,500 tons of carbon dioxide from being released into the atmosphere in the US each year. This shows how effective wind energy is and the effects it has. There is also energy from coal which is a non-renewable energy source because it takes millions of years to create and the problem with this is that coal is running out fast, so once it has run out then there is no other way for us to do many of the things we do and use daily without coal. Lastly, bio fuels, including ethanol, are clean-burning, biodegradable and made from renewable resources. In addition to being used as fuel for transportation, bio fuel can be converted to other useful forms of energy, including methane gas and heat.
These different methods of energy production, show exactly how efficient they are, and which energy source is more efficient than the other. In comparison, I would say that the wind energy is one of the most reliable meanings saving coast, being renewable etc, but for generating electricity I would say that the hydro electric power is the most efficient. The reason for this is because Hydro-electric power, using the potential energy of rivers, now supplies 17.5% of the world's electricity, this shows how useful it is and also because it is available in many forms, potential energy from high heads of water retained in dams, kinetic energy from current flow in rivers and tidal barrages, and kinetic energy also from the movement of waves on relatively static water masses. This is why I would use this method for generating electricity.