Tutor profile: Gabrielle T.
Questions
Subject: Writing
Choose how the following sentences should be ordered to make a paragraph. Explain your reasoning. 1) This information can include, but is not limited to, a summary, evaluation, and explanation of context or relevance. 2) Therefore, it should help with both your research proposal and the research paper itself. 3) The purpose of the annotated bibliography is to start finding sources, evaluating those sources, and determining how the ideas in those sources can be used in your research paper. 4) In general, a bibliography is simply a list of sources. 5) The annotated bibliography, however, goes one step further and gives more information about each source.
1) This sentence expands on the "more information" from sentence 5, so it should be placed after it. 2) This is a good summary sentence to end the paragraph. The transition word "therefore" is usually used to indicate a conclusion or inference from earlier sentences. 3) This sentence gives more information about the paragraph topic (annotated bibliographies) and would be useful in the middle of the paragraph. 4) This is a general statement that should be early in the paragraph. 5) This sentence is also a general statement. The word "however" implies that it is being compared to something previously mentioned. In this case, annotated bibliographies are being compared to general bibliographies mentioned in sentence 4, so this one should come after it. So the order should be: 4, 5, 1, 3, 2
Subject: Physics
Hybrid gas-electric cars turn mechanical energy into electrical energy which can be used at a later time to power the car. This helps reduce gas usage. a) While driving, during what kind of motion would the most energy be converted into electrical energy and stored? Explain. b) You are driving around the city and reach a red light. Initially, you are following the speed limit and traveling at 30 mph. It takes you 10 m to stop the car. Your car has a mass of 2000 kg. If the energy lost while braking is stored in a capacitor at 12 V, what is its capacitance?
a) In order to have energy to store in the form of electrical energy, we need to have energy that isn't being used for the car's motion (in other words, its kinetic energy). If the car is traveling at a constant speed on a flat surface, then no energy is being converted between potential and kinetic energy. When accelerating, the engine is doing work, and therefore using energy, to increase the car's kinetic energy. When the car is slowing down or braking, friction is doing work, and energy is lost as heat. This "lost energy" could instead be turned into electrical energy rather than heat and stored for later use. b) Since we are converting kinetic energy into electrical energy, we have -Ue = Kf - Ki, or electrical potential energy equals the change in kinetic energy. Since the car ends in no motion, Kf=0. Its initial kinetic energy is dependent on its initial speed (vi) with the relation, Ki=1/2*m*vi^2. Plugging in the numbers, we get Ue = Ki - Kf = 180 kJ - 0 = 180 kJ. The relation between potential energy and capacitance is Ue = 1/2*C*V^2. This relation can be rearranged to solve for the capacitance, C = 2*Ue/V^2. Plugging in the numbers, we get C = 2.5 kF.
Subject: Algebra
Solve for x in the following: x*log3 + b = 10 - x/a
So where do we start? First, we need to isolate all terms with x. Let's put the terms with x on the left and the ones without x on the right. The first term on the left has x, so it's good where it is. The second term does not have an x, so we need to move it to the other side. How do we do that? Well, since it is an added term, we can subtract it from both sides, which gives us: x*log3 = 10 - x/a - b. Now, let's look at the right side. The first and last terms do not have an x, so those are good. The second term does have an x, so let's move it to the left side. In this case, it is a negative (or subtracted) term, so we need to add it to both sides. This gives us: x*log3 + x/a = 10 - b. Now that we have all terms with an x on one side, we can factor out the x using parentheses: x*(log3 + 1/a) = 10 - b. Lastly, to isolate x by itself, we need to move the parentheses to the other side. Since the (log3 + 1/a) is multiplied to x, we move it by dividing both sides. This leaves us with the solution: x = (10 - b)/(log3 + 1/a) .
Contact tutor
needs and Gabrielle will reply soon.