1. What is total internal reflection and why is it important in optical fibers? What is the critical angle?
2. Does a diverging lens have a focus point?
3. What type of lens, diverging or converging, would you use for a magnifying glass? Explain.
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A sphere with a diameter of 70 cm is held at a temperature of 290
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As a coffee enthusiast you wish to keep your coffee as hot as possible for as long as possible. You wish to find the rate of heat loss of a typical coffee mug. Assume the mug to be a cylinder which has a lid made out of the same material as the rest of the cylinder, and the thickness of the walls is 1.34 cm. If the coffee in the mug is 79.2 °C and the room temperature is 24.0 °C how much more heat does the mug lose through conduction than from radiated energy. See the hint below for important constants.
Assume that the thermal conductivity of all sides of the mug is 0.850 W/m·C, that the mug has an emissivity of 0.760 and the Stefan-Boltzmann Constant is 5.67 × 10-8 W/m2·K4. Remember to properly convert all units and to include all surfaces of the mug.
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A 0.36-kg object connected to a light spring with a force constant of 23.4 N/m oscillates on a frictionless horizontal surface. The spring is compressed 4.0 cm and released from rest. (b) Determine the speed of the object when the spring is compressed 1.5 cm. (d) For what value of x does the speed equal one-half the maximum speed?
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A 31.0-kg child on a 3.00-m-long swing is released from rest when the ropes of the swing make an angle of 31.0° with the vertical.
(a) Neglecting friction, find the child's speed at the lowest position.
(b) If the actual speed of the child at the lowest position is 2.50 m/s, what is the mechanical energy lost due to friction?
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Here is a typical question which I have been asked many times while giving public lectures in various places. While I know one of the paths like Diploma, Masters and PhD but sometimes this is not so obvious for that eager young person who thinks to go on that path. So what that would be?
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Needing a solution to this question.
5) A rope of mass m and length ℓ hangs from a ceiling. Show that the wave speed on the rope a distance y above the lower end is v= Square root of gy (10). Would such a hanging rope support a “wave”, as per our definition in Q1? Explain in words?
******NOTE this is question one (Q1). It has been solved already. Just for reference. Thanks
Q1) A good definition of a “wave” is a disturbance of a continuous medium that propagates with a fixed shape at constant velocity. (Griffiths, 1999, Introduction to Electrodynamics). Another way of saying this is the medium (e.g. a string, water, or air) will only propagate a wave as long as its shape satisfies the wave equation: d^2 f/dx^2 =1/v^2 . d^2 f/dt^2 a) Show explicitly whether the displacement function f(x,t) = A sin(kx) cos(ωt) will be propagated in a medium as a wave or not. (5) b) Do the same for the function f(x,t) = A exp(−b(bx2 + vt)) (5) c) Could a string support a disturbance of the form f(x,t)=Asin(kx)cos(x−ωt) as a wave? Your professor will show you what this looks like in class and you will immediately
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1 Vince, a 180 lb athlete, performs the vertical jump test. His
standing reach is 82 inches, and his highest jump is 107 inches.
What is his power output in Watts (1 Watt = 0.1020 kgm/sec.)? Round
your answer to the first decimal place.
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Question 2 Turtle (220 lb individual) performs the Margaria-Kalamen leg power test (stair test). His time between the 3rd and 9th steps is 0.75 seconds (each step is 6 inches in height). What is his power output in kgm/sec? Round your answer to the nearest whole number.
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Question 3 Jennifer is a 140 lb athlete who performed the Margaria-Kalamen leg power test (stair test). Her time between the 3rd and 9th steps was 0.58 seconds (each step is 7 inches in height). What was her power output in Watts (1 Watt = 0.1020 kgm/sec.)? Round your answer to the nearest whole number.
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Question 4 Among the three energy systems which one produces ATP at the fastest rate?
5) Amanda is a 115 lb athlete who performed the 30-second Wingate test. Her peak power output was 559 Watts, and her lowest power output was 332 Watts. What was her anaerobic fatigue (percent decline in power output)? Round your answer to the first decimal place.
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Radio Antenna: how waves are created, through what mediums, and what types of waves (longitudinal or transverse) -how different frequencies, wavelengths, and amplitudes of waves affect the results. -If constructive/destructive interference occurs. -Most importantly - how resonance plays a part. -Other interesting info.
200 words
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A boxcar of length 10.1 m and height 2.4 m is at rest on frictionless rails. Inside the boxcar (whose mass when empty is 3600 kg) a tank containing 1700 kg of water is located at the left end. The tank is 1.0 m long and 2.4 m tall. At some point the walls of the tank start to leak, and the water fills the floor of the boxcar uniformly. Assume that all the water stays in the boxcar.
A. After all the water has leaked out what will be the final velocity of the boxcar? (Take movement to the right as positive. Assume that the mass of the boxcar is evenly distributed.)
B. What is the displacement of the boxcar 9 s after the water has settled in the bottom. (Take positive displacement as being to the right.)
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10. Klay Thompson has an amazingly consistent 3 point shot. He consistently releases from let's say 3.0 meters above the ground to enter a hoop 22 ft away (note units). The hoop is 10 ft off the ground.
a. If he shoots with a release angle of 30 degrees, how fast is the ball as it leaves his hands?
b. The same shot is attempted, at the same angle, but bounces off the back of the rim. It went 0.15m past what he wanted. What was the speed on release for this shot?
c. (Opinion) Would you rather be able to do this problem via repetition and feel like Klay does? Or would you rather go through the numbers so that you could program a robot to shoot a ball better than Klay or Curry or Jordan?
( We are doing projectile motion right now )
I also I converted the feet to meters i noticed the hoop is 3 meters(rounded) and so is where Klay shoots his ball.
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A parachutist bails out and freely falls 69 m. Then the parachute opens, and thereafter she decelerates at 2.6 m/s2. She reaches the ground with a speed of 3.3 m/s. (a) How long is the parachutist in the air? (b) At what height does the fall begin?
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a) A child slides down a water slide at an amusement park from an initial height h. The slide can be considered frictionless because of the water flowing down it. Can the equation for conservation of mechanical energy be used on the child?
YesNo
(b) Is the mass of the child a factor in determining his speed at
the bottom of the slide?
YesNo
(c) The child drops straight down rather than following the curved
ramp of the slide. In which case will he be traveling faster at
ground level?
following the curved rampdropping straight down same speed in either case
(d) If friction is present, how would the conservation-of-energy
equation be modified?
(e) Find the maximum speed of the child when the slide is
frictionless if the initial height of the slide is 13.5 m. (Assume
the child is initially at rest.)
m/s
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For College Physics. Please explain in paragraph form. Please type it out as I cannot read some written hand writing
Respond to the following: In your OWN words DON'T copy from an online course.
Explain vector, scalar, speed, velocity, and linear acceleration. Also give examples.
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