Quiz 4

Choose the correct answer

Cylindrical metallic parabolic trough solar thermal collectors. 1. Does not rotate. 2. It rotates around one axis only. 3. It rotates around two axes only. 4. They can produce a temperature of20-100 °C. 5. They can produce a temperature of200-400 °C. 6. They can produce a temperature of2000-4000 °C. O 1 + 4 only. O 2 + 5 only. 2 + 6 only O 3 + 5 only.

In a fluorescence-lifetime experiment, a very short pulse of light is used to excite a sample. Then the intensity of the fluorescence is recorded as a function of time. Suppose we study a dansyl fluorophore. The intensity of the fluorescent light versus time is as follows: Fluorescence intensity Time (ns) 1.1 x 104 4.9 x 103 5 2.3 x 103 10 1.3 x 103 15 5.6 x 102 20 Part A What is the observed fluorescence lifetime? Express your answer to two significant figures and include the appropriate units. T = 6.9 ns Submit Previous Answers Correct Part B The fluorescence quantum yield under the same conditions was determined to be 0.7. What is the intrinsic rate constant for radiative fluorescence decay? Express your answer to two significant figures and include the appropriate units. НА ? Value TO Units Submit Previous Answers Request Answer X Incorrect; Try Again; 4 attempts remaining Part C It has been determined separately that when the dansyl chromophore is 20 A away from the 11-cis-retinal…

Describe the graph of the oscilloscope

a)Does this Oscilloscope trigger on the rising or falling edge of the signal? b) At what voltage does the trigger signal reach that starts the Oscilloscope ‘Sweep’? c) What is the amplitude of the signal on Channel 1? d) What is the amplitude of the signal on Channel 2? e) What is the period of the signal on Channel 1?

An oscilloscope has a rise time of 72 ns. Calculate the highest-frequency sine wave that the scope can display. Round the final answer to two decimal places. MHz

lease draw the same sine wave that would be displayed on different time per division and volts per division settings on the oscilloscope.  the time per division is displayed at the center bottom of the each screen and the volts per division is displayed on the bottom left of the screen. The wave you will be drawing will be a sine wave with frequency of 1000 Hz and an amplitude of 3 V. The wave you will be drawing will have the equation: 3sin(2π⋅1000t)

The main purpose of an oscilloscope is to graph an electrical signal as it varies over time. Most scopes produce a two-dimensional graph with time on the x-axis and voltage on the y-axis. The voltage waveform on the screen looks as shown in the figure below. Here, the vertical resolution of the oscilloscope is set up to be 2 mV/division and the horizontal resolution is 2 ms/division. Time 1. Determine the peak-to-peak amplitude of the wave. Voltage

Number 20