Please answer and provide an explanation with the necessary formula. Thank you in advance,
1. A 200kg block slides down a rough inclined plane of length 2.5m inclined at 20 degrees. At the bottom of the plane the speed of the block is 3.15 m/s. Initially the block was at rest. What is the change in the internal energy of the system? What is the frictional force?
2. A sled at rest in snow seated with two children with total mass of 50kg. You pull the sled with a rope that makes an angle of 42 degrees with the horizontal. The coefficient of kinetic friction is 0.150 and the tension in the rope is 150 N. What is the speed of the sled after it has moved through 3.5m?
3. Oxygen gas has a molar mass of 32 g/mol and carbon dioxide has a molar mass of 44.05 g/mol. What is the rms speed of the oxygen molecule at 300? If the carbon dioxide molecule has the same rms speed as oxygen molecule, what is the temperature of the carbon dioxide molecule?
4. A U tube contains a liquid of unknown density. An oil of density 800 kg m/s is poured into the tube in one of the arm and the oil column is 12 cm high. The air interface is 5 cm above the liquid level in the other. What is the density of the liquid?
5. A uniform ladder of weigh 75 N leans against a frictionless vertical wall. The foot of the ladder is 2.5m away from the wall. The length of the ladder is 5m. A fireman of weigh 700 N is on the ladder at a distance of 4m along the ladder. What is the magnitude and direction of the force exerted by the floor and ladder?
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n = 2.35 mol of Hydrogen gas is initially at T = 322 K temperature and pi = 2.86×105 Pa pressure. The gas is then reversibly and isothermally compressed until its pressure reaches pf = 8.33×105 Pa. What is the volume of the gas at the end of the compression process?
How much work did the external force perform?
How much heat did the gas emit?
How much entropy did the gas emit?
What would be the temperature of the gas, if the gas was allowed to adiabatically expand back to its original pressure?
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3. A 98.0 kg hockey player skating at 2.12 m/s 32° S of W is body checked by an 87.0 kg opponent who is skating at 1.40 m/s 42° N of E. They collide inelastically and stick together. a. What is the velocity of the pair immediately after the collision? Solve using both methods. .
Trig. Method (include a vector diagram)
Component Method (show all work)
b. Determine the impulse imparted to the 98.0 kg player. Show a complete vector diagram and label your answer.
c. From what you know about Impulse, what would the Impulse for the 87.0 kg player be? Provide both magnitude and direction. (you need not calculate if you understand the concepts)
d. State what you found out for questions b and c above and justify your results using I = Favg t. State any of the appropriate Newton’s Laws to help explain. No calculations are necessary. Simply justify what you found out from (b) and (c) by using the other equation for Impulse, I = Favg t.
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Part I: Light Beams
In Part I(b), as you moved the focal point from 50 to 200 on the
optical axis, the lens ---Select--- became fatter did
not change shape became slimmer .
In Part I(c), the reason the colored rays are dispersed so that you
can see individual colored rays is because
the ---Select--- index of polarization index of
reflection index of refraction is different for each color of the
spectrum.
This phenomenon is referred to as ---Select--- immersion
dispersion specular reflection of light.
Part II: Ray Diagram
Step 1200
100
50
200
100
50
300
150
50
100
75
50
(a) The image was ---Select--- virtual real .
(b) The image distance was ---Select--- positive
negative neither positive nor negative .
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Give an example of how the 1st Law of Thermodynamics relates to metabolism in humans
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What minimum amount of electromagnetic energy is needed to produce an electron and a positron together? A positron is a particle with the same mass as an electron, but has the opposite charge.
E=?
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A cube of ice is taken from the freezer at -9.5?Cand placed in a 95-g aluminum calorimeter filled with 310g of water at room temperature of20.0 ?C. The final situation is observed to be all water at 15.0?C. The specific heat of ice is2100 J/kg?C?, the specific heat of aluminum is900 J/kg?C?, the specific heat of water is is4186 J/kg?C?, the heat of fusion of water is333 kJ/Kg. What was the mass of the ice cube?
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What is centripetal acceleration? What is centripetal force? What purpose does centripetal force serve, and how can it be provided?
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How far away is a star that has a parallax of 0.03 seconds of arc? 0.3 parsecs/333.3 parsecs/33.3 parsecs/3.3 parsecs
If you took a measuremnt for a stars position in March, using parallex when is the optimum month for the next measurement? Sept /Oct/ April/ any month
The nearest stars have been catalogued using parallax what is the range of the stars found in this catalogue? 4 to 100 parsecs/ 2 to 1000 parsecs/ 10 to 50 parsecs/ all stars out to 500 parsecs
Compared to close stars, the parallax angle is ________________ for more distant stars. Smaller/ larger/ the same as/ unrelated to distance of stars
Why are astronomers much more interested in the luminosity of a star than its apparent brightness? because the luminosity tells us how bright a star really is, while apparent brightness only tells us how bright it happens to look from Earth/because luminosity can be measured exactly, but apparent brightness can only be roughly estimated/because the luminosity also tells us what elements the star is made of, while apparent brightness cannot tell us a star's chemical make
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3. A rigid uniform disk (moment of inertia I = 1/2 m R2) has a mass m = 10 Kg and radius R = 2 m, it is free to rotate around a fixed axis passing through its center and is at rest at t = 0 s. A constant force F = 20 N is applied halfway between the center and the edge of the disk, in a direction perpendicular to the disk radius.
(i) Calculate the torque, the angular acceleration, the angular velocity and the rotation angle of the disk after t = 10 s. τ=20 Nm ; α=1 s-2 ; ω=10 s-1 ; Δθ=50 (rad)
(ii) Calculate the kinetic energy and the angular momentum of the disk at t = 10 s. K=1000 J ; L = 200 Js
(iii) Show that the relationships between torque, work, kinetic energy and angular momentum are numerically satisfied. W = τ∗Δθ = 20 Nm*50 = 1000 J ; Kf-Ki = 1000 J
τ∗Δt = 20 Nm*10s = 200 Js ; Lf-Li = 200 Js
THE ANSWERS ARE IN BOLD, COULD YOU PLEASE SHOW THE WORKING NEEDED FOR THIS QUESTION?
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At what separation distance can a proton hover above another proton due to electrostatic repulsion? Hint: Compare gravity to electrostatic repulsion. Please show step by step and explain how you got the numbers. Thanks
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It has been proposed that we could explore Mars using inflated balloons to hover just above the surface. The buoyancy of the atmosphere would keep the balloon aloft. The density of the Martian atmosphere is 0.0154 kg/m3 (although this varies with temperature). Suppose we construct these balloons of a thin but tough plastic having a density such that each square meter has a mass of 4.90 g. We inflate them with a very light gas whose mass we can neglect.
Part A
What should be the radius of these balloons so they just hover above the surface of Mars?
Part B
What should be the mass of these balloons so they just hover above the surface of Mars?
Part C
If we released one of the balloons from part A on earth, where the atmospheric density is 1.20 kg/m3, what would be its initial acceleration assuming it was the same size as on Mars?
Part B What should be the mass of these balloons so they just hover above the surface of Mars?
SubmitMy AnswersGive Up Part C If we released one of the balloons from part A on earth, where the atmospheric density is 1.20 kg/m3, what would be its initial acceleration assuming it was the same size as on Mars?
Part D Would it go up or down? |
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two skaters collide and embrace, in a completely inelastic collision. boomer, whose mass is 83 kg, is originally moving east with v=6.2km/hr. sooner whose. mass is 55kg, is originally moving north with v=7.8km/hr. (a) what is the velocity of the couple after impact? (b) what is the velocity of the center of mass of two skaters before and aafter collision? (c) what is the fractional change in the Kinect energy of the skaters because of the collision?
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An ancient club is found that contains 160 g of pure carbon and has an activity of 6.5 decays per second. Determine its age assuming that in living trees the ratio of ( 14 C 12 C ) atoms is about 1.40 × 10 − 12 . Note that the half life of carbon-14 is 5700 years and the Avogadro number is 6.02 × 10 23.
Answer in years
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For what range of object positions does a bi-convex lens of focal length f form a real image?
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