Value Of e/m

The purpose of this experiment was to study the magnetic field of the Helmholtz coils in the form of electron trajectories and determine the value of e / m. Determining the value of e / m is done by measuring the diameter of a circle using a scale measuring the electron trajectories contained in the unit for the Helmholtz potential difference constant, strong flow of coil turns and the potential difference changes, strong constant coil current. The calculation of the value of e / m done analytically and graphs. The value of e / m with analytical calculations and graphs during the constant potential difference, strong currents changed each coil is 3.07 x 1011C / kg and 4.30 x 10 11C / kg, while at constant coil current and potential difference change the value of e / m respectively are 2.60 x 1010 C / kg and 1.46 x 10 11C / kg. By reference to the value of e / m is 1.76 × 1011 C / kg (Beiser, A.1990).

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What does the agreement actually say?

One day, when historians look back to pick the time when the world finally woke up and decided to address global warming, that time may well be the fall of 2014. First, the march in New York drew 400,000 people and many thousands more across the globe to demand that our leaders take action on climate change. And today, the United States and China announced a truly historic agreement to cut emissions of carbon dioxide. The agreement is a welcome breakthrough. It is very promising that the world’s two biggest economies—together responsible for roughly 40 percent of global emissions—have agreed to cut their emissions. Specifically, President Obama committed the U.S to reducing its emissions to 25-28 percent below 2005 levels by 2025, which is feasible using proven and cost-effective technologies such as renewable energy and electric vehicles. And China has pledged for the first time that its total emissions will peak no later than 2030, a sharp break from the current trajectory in which emissions from China continue to rise each year. To help make good on that pledge, China has also agreed to get 20 percent of its energy from renewable or nuclear sources by 2030. This agreement removes the biggest stumbling block to a global climate accord, namely the unwillingness of the United States to act without a commitment from China (and vice-versa), and the unwillingness of other countries to act without strong commitments from both countries. Global warming is the ultimate example of the “tragedy of the commons” in which the health of a shared resource (in this case, the earth’s atmosphere) depends upon many individual nations taking action collectively, with no individual nation wanting to pay the cost unless it can be assured that other responsible counterparts are also doing their fair share. The only effective antidote to this dynamic is real leadership, and that is precisely what United States and China have just shown. Now that they have stepped up to the plate, accompanied by the European Union, which has pledged a forty percent

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