A 27 g ball is fired horizontally with speed v0 toward a 106 g ball hanging motionless from a 1.13-m-long string. The balls undergo a head-on, perfectly elastic collision, after which the 106 g ball swings out to a maximum angle θmax=57°. What was v0?
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(5) Describe the consequences of a 10-km asteroid striking Earth?
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Question 7 a. The radius of curvature of a plano-convex lens is measured to be 2 metres, and the focal length in air (n = 1) is measured to be 4 metres. i. What is the power of the lens? [2 marks] ii. What is the refractive index of the lens material? [4 marks] b. A toy Dalek is placed 40 cm in front of a converging lens of focal length f1 = 20 cm; another converging lens 60 cm behind the first has a focal length of f2 = 10 cm. i. Draw a ray trace diagram for this optical system [4 marks] ii. Show where the image produced by the first lens appears on your diagram. Is it a real or virtual image? [3 marks] iii. What is the magnification of the object at the first image? [1 marks] iv. Show where the final image appears on your diagram. Is it a real or virtual image? [3 marks] v. What is the magnification of the first image at the final image? [1 mark] vi. What is the magnification of the object at the final image? [2 marks]
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An unmarked police car traveling a constant 80.0 km/h is passed by a speeder traveling 115 km/h . Precisely 1.50 s after the speeder passes, the police officer steps on the accelerator; if the police car's acceleration is 2.50 m/s2 , how much time passes before the police car overtakes the speeder after the speeder passes (assumed moving at constant speed)?
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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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