[Q]: Given the background: Charging an object by touching it with another charged object is called charging by conduction. By bringing a charged object into contact with an uncharged object, some electrons will migrate to even out the charge on both objects. Charging by conduction gives the previously uncharged object a permanent charge. An uncharged object can also be charged using a method called charging by induction . This process allows a change in charge without actually touching the charged and uncharged objects to each other. Imagine a negatively charged rod held near the knob, but not touching. If we place a finger on the knob, some of the electrons will escape into our body, instead of down the stem and into the leaves. When both our finger and the negatively charged rod are removed, the previously uncharged electroscope now has a slight positive charge. It was charged by induction. Notice that charging by induction causes the newly charged object to have the opposite charge as the originally charged object, while charging by conduction gives them both the same charge. and the situation: With my previous cell phone, in order to charge it I would have a plug the charger into the wall and the plug the cord into my phone to connect it to the electric source. With my new phone, I just place the phone into the charging dock and my phone is charge wirelessly. Answer the following question: Was my previous cell phone being charge using induction or conduction?
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[A]: conduction

[Q]: Given the background: Some materials have negative heats of solution; the dissolution of one of these solutes in water is an exothermic process. Heat is released, causing a net increase in the temperature of the solution. Conversely, other substances have positive heats of solution. For example, the dissolution of potassium nitrate in water is an endothermic process. The resulting absorption of energy causes the solution to become colder. Calculations involving heats of solutions follow the same basic approach that we have used with other enthalpy problems. and the situation: John is conducting an experiment in his chemistry lab. His goal is to find a chemical solution that can regulate temperature. To that end, he considered two processes, process A and process B. Process A is an exothermic process, but process B is an endothermic process. Answer the following question: In wich process heat will be absorbed, process A or process B?
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[A]: process B

[Q]: Given the background: There is a zone of the atmosphere in which ozone absorbs some 98% of non-ionizing but dangerous UV-C and UV-B. This so-called ozone layer starts at about 20 miles (32 km) and extends upward. Some of the ultraviolet spectrum that does reach the ground (the part that begins above energies of 3.1 eV, a wavelength less than 400 nm) is non-ionizing, but is still biologically hazardous due to the ability of single photons of this energy to cause electronic excitation in biological molecules, and thus damage them by means of unwanted reactions. An example is the formation of pyrimidine dimers in DNA, which begins at wavelengths below 365 nm (3.4 eV), which is well below ionization energy. This property gives the ultraviolet spectrum some of the dangers of ionizing radiation in biological systems without actual ionization occurring. In contrast, visible light and longer-wavelength electromagnetic radiation, such as infrared, microwaves, and radio waves, consists of photons with too little energy to cause damaging molecular excitation, and thus this radiation is far less hazardous per unit of energy. and the situation: John was interested in the Sun's radiations that Earth receives. One of the radiations was in the ultraviolet spectrum. He categorized it as spec A. The other radiation was the visible light. He categorized it as spec B. He then searched online to find the pros and cons of each of them. Answer the following question: Which radiation would be less hazardous, spec A or spec B?
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[A]: spec B

[Q]: Given the background: Figure B above shows an important relationship between the wavelength and frequency of a wave. The top wave clearly has a shorter wavelength than the second wave. However, if you picture yourself at a stationary point watching these waves pass by, more waves of the first kind would pass by in a given amount of time. Thus the frequency of the first waves is greater than that of the second waves. Wavelength and frequency are therefore inversely related. As the wavelength of a wave increases, its frequency decreases. The equation that relates the two is and the situation: Bill is working in a sound studio recording sound effects for a short film that he is working on. Some of the sounds he captured have a very high frequency and others are very low frequency. When he is done he begins to edit the sound with a computer program. Patrick is measuring voltages with an oscilloscope. As he is testing various objects, he notices a number of frequency changes on the display. Answer the following question: When Patrick saw a high frequency on his oscilloscope were the wavelengths long or short?
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[A]:
short