Explain how photodiode array(PDA)-based single beam UV-Vis spectrophotometer works(illustrate your explanation by drawing a schematic diagram)

What is the main advantage of the PDA-based (reverse optics) single beam instruments compared to the conventional single beam ones?

There are two speakers at the front of the room. Each is outputting a 250Hz pure tone. For each of the following situations, will you hear constructive interference (a loud noise) or destructive interference (soft or no noise). ? represents the wavelength of the 250Hz tone.

You are 3? away from speaker A; 2? away from speaker B and at the speakers the waves are exactly in phase.

You are 3? away from speaker A; 2.5? away from speaker B and at the speakers the waves are exactly in phase.

You are 3? away from speaker A; 4? away from speaker B and at the speakers the waves are exactly out of phase.

You are 3? away from speaker A; 2.5? away from speaker B and at the speakers the waves are exactly out of phase.

M4. Discussion: Frictionless World

Topic

In this module, we examined the concept of friction and how it affects everything we do. Air resistance is an important type of friction that you don’t want to forget about as you prepare your post. Consider what the world would be like without friction. For example, in a world without friction, the pitcher in a baseball game can still pitch the ball because he can push off the pitching rubber. The pitching rubber is the rubber slab atop the pitching mound that a pitcher uses to push off to gain velocity. But what happens when the batter swings or when the ball hits the catcher’s mitt?

Now, think of one of your favorite sports or another activity you enjoy. How would the action of that activity be different in a world without friction? In your initial post to the discussion, describe your activity and then respond to the following:

1. Describe at least three ways your activity would change if friction were taken out of the scenario.
2. Does friction make it easier or harder to participate in your activity?
3. What are some advantages and disadvantages that you might encounter if there wasn’t friction in our world?

Finally, be sure to respond to at least two of your peers’ discussion posts.

A thin film of MGF₂ has a refractive index of n = 1.38 and it is deposited on glass as an anti-reflective layer of light with a wavelength of 580nm which falls in the normal direction towards the film. What wavelength is minimally reflected when the light falls at 45 ° towards the film?

3) A 2 kg block is sliding at an initial speed of 10 m/s across a surface, encountering a constant friction force of 7 N. How much work is done on the block after it slides 22 cm?

Answer:  

Hint: Does the block gain or lose energy during this process? What sign does this imply for the work done on it?

4) How fast is the block moving after sliding 22 cm?

Answer:  

Hint: You can treat the block like a simple particle. What kind of energy does it have and how is this affected by the work done on it?

5) What's the total distance the block travels before coming to rest?

Correct, computer gets: 14.29 m

6) What is the average power of friction on the block over the time it takes the block to come to rest?

Answer:  


7) What was the instantaneous power of friction on the block after it slid the first 22 cm?

Answer

Im stuck on questions (

Questions 2a-c (refer to a 0.250 kg pendulum, and then answer 2a-d)

A match 5 cm long is placed 20 cm in front of a concave mirror whose focal length is 50 cm. Find the location, size, and nature of the image.

)

Identify a few contemporary societal facets that are affected so heavily by innovation in engineering and the sciences.

3. In ion mobility spectrometer, the ions are accelerated under a constant electric field in a cylindrical tube and the time of flight of the ions in this tube is measured. The ions are detected by using a sensor at the end of the tube. a) What type of sensor can be used to detect the ions? b) The experiment is performed at high frequencies to be able to decrease the effect of the noise. What type of noises can be present in this experiment?c) During the experiment, many devices are used together. What type of grounding can be used for this experimental setup to be able to prevent floating grounds and crosstalks? d)

The mobility of the ions is given as ? = ? ? 1 ? , where l, E and t are the length of the tube, the electric field strength and the time of flight, respectively. The data given in the table belongs to a specific type of spectrometer. By plotting this data, find the required length of the tube for an electric field strength of 10^4 V/cm.

A.Please answer these questions:

1) For which n does the complete graph Kn have an Eulerian circuit?

2) For which n does the complete graph Kn have a Hamiltonian Cycle?

3）For which r, s does the complete bipartite graph Kr,s have an Eulerian circuit?

4） For which r, s does the complete bipartite graph Kr,s have a Hamiltonian Cycle?

5）Find a graph that has an Eulerian circuit but no Hamiltonian Cycle?

6）Find a graph that has a Hamiltonian Cycle but no Eulerian circuit?

. It is often said that “water seeks its level.” Explain

A bumper car with mass m₁ = 122 kg is moving to the right with a velocity of v₁ = 4.5 m/s. A second bumper car with mass m₂ = 2m₁ = 244 kg is at rest. The two have an elastic collision and the first bumper car rebounds backwards at a speed that is 1/3 of its original speed (1.5 m/s). Assume the surface is frictionless.

1) What is the change in momentum of bumper car 1? (let the positive direction be to the right)

2) What is the change in momentum of BOTH bumper cars combined?

3) What is the change in momentum of bumper car 2?

4) What is the final velocity of car 2?

5) What is the change in energy of bumper car 1?

6) What is the change in energy of BOTH bumper cars combined?

7) What is the change in energy of bumper car 2?

7.15 Channel equalization. We suppose that u1, . . . , um is a signal (time series) that is trans- mitted (for example by radio). A receiver receives the signal y = c ∗ u, where the n-vector c is called the channel impulse response. In most applications n is small, e.g., under 10, and m is much larger. An equalizer is a k-vector h that satisfies h∗c ≈ e1, the first unit vector of length n + k − 1. The receiver equalizes the received signal y by convolving it with the equalizer to obtain z = h ∗ y.

(a) How are z (the equalized received signal) and u (the original transmitted signal) related? Hint. Recall that h∗(c∗u) = (h∗c)∗u.

(b) Numerical example. Generate a signal u of length m = 50, with each entry a random value that is either −1 or +1. Plot u and y = c ∗ u, with c = (1,0.7,−0.3). Also plot the equalized signal z = h ∗ y, with

h = (0.9, −0.5, 0.5, −0.4, 0.3, −0.3, 0.2, −0.1).

propagate errors for magnitude and theta.

magnitude(aka R) = sqrt(Rx²+Ry²)

tetha = arctan(Ry/Rx)

unclear on how to get the equation delta R and delta theta.

In an insulating box, there is a 140.0g block of lead whose temperature is 100K and a 70.0g block of tungsten whose temperature is 300K. (a) What is the equilibrium temperature of the two-block system? (b) What is the change in the internal energy of the system between the initial and the equilibrium state? (c) What is the change in the entropy of the system? (specific heat of tungsten: 0.0321cal/g · K, molar specific heat of tungsten: 24.8J/mol · K, specific heat of lead: 0.0305cal/g ·K, molar specific heat of lead: 26.5J/mol·K