Master Physics with Fun Quizzes & Brain Teasers!

ssuming the same total time of flight, what is the difference between the maximum height of the ball thrown on the moon, hm , and the maximum height of an identical ball thrown on the earth, he ? ignore the effects of the earth's atmosphere.
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the question of why is the universe so perfectly close to critical density is known as the problem.
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Question: What factors affect the angle of the pith balls?1. Observe : If necessary, turn on Show angle. What is the current value of ? 2. Predict: Predict the effect of each change on the angle of the pith balls (). Fill in each blank with either " increases" or " decreases." Explain each of your predictions. A. g increases: g decreases: .Explain: B. Mass increases: Mass decreases: Explain: C. Length (L) increases: L decreases: .Explain: 3. Test: Use the Gizmo to test each of your predictions. Write your results below. A. g increases: g decreases: B. Mass increases: Mass decreases: C. L increases: L decreases: 4. Interpret: How is increasing the mass of the pith balls similar to increasing the value of g?5. Think and discuss: Why does increasing the length of the string cause the angle of the pith balls to decrease? (Hint: Why wouldnt you expect the angle to stay the same?)
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range, variance, and standard deviation are measurements of: a. gradations of quality. b. sampling error. c. intensity. d. dispersion. e. quantity
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a horizontal spring has a spring constant of 80.0 n/m. what force must be applied to the spring to compress it by 4.0 cm?
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Batman is leaping from building to building in pursuit of Joker. The rooftop of the next building is 10 meters away and 15 meters below the roof he is currently on. If he jumps with a velocity of 5.10 m/s at an angle of 20 degrees above the horizontal, will he make it? (a) what are the components of the initial velocity? (b) How long will he be in the air if he successfully lands on the lower roof? (c) How far will he travel horizontally in the time it takes to land on the lower roof? (d) Compare your answer from (c) to the horizontal distance to the roof of the next building. Does Batman make the jump?
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which of the following physical principles always holds true to the best of our current scientific understanding, regardless of the choice of system?
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what is the distance of a star with apparent magnitude of m=20 and absolute magnitude of m=0 group of answer choices 10 pc 10,000pc 100,000pc 1,000,000pc
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Police use the formula s=sqrt(30fd) to estimate the speed (s) of a car just before it skids. In this formula (s) is the speed of the car, (d) is the distance the car skidded in feet, and (f) represents the coefficient of friction. The value of (f) depends on the condition and type of road surface. We know f=.35 when the road is wet concrete and 0.95 on a dry concrete road.You are given the job of investigator! You will be given the measurements of two skidding cars involved in an accident. Determine the speed of each car prior to the skid.Car A: Skid was measured to be 32 feet. Car B: Skid was measured to be 43 feet.a. What is the exact speed in radical form and exponential form?b. What is the estimated speed rounded to the nearest tenth?c. You know that you should keep a safe following distance when following other cars on a roadway. How long should your following distance be if both you and the car in front of you are travelling at 55 mph?
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The electron gun in a television tube uses a uniform electric field to accelerate electrons from rest to 4.5107m/s in a distance of 1.2 cm.What is the electric field strength?
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assume that a chunk of potassium weighing 7.55 g is dropped into 400.0 g of water at 25.0 c. what is the final temperature of the water if all the heat released is used to warm the water?
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You dive straight down into a pool of water. You hit the water with a speed of 5.0 m/s, and your mass is 75 kg. Assuming the drag force of the form FD=(1.10104 kg/s)v, how long does it take you to reach 2% of your original speed? (Ignore effects of buoyancy.)
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A steel loop ABCD of length 5 ft and of 3838 -in. diameter is placed as shown around a 1-in.-diameter aluminum rod AC. Cables BE and DF, each of 1212 -in. diameter, are used to apply the load Q. Knowing that the ultimate strength of the steel used for the loop and the cables is 75 ksi, and that the ultimate strength of the aluminum used for the rod is 45 ksi, determine the largest load Q that can be applied if an overall factor of safety of 3 is desired. The largest load Q that can be applied is kips.
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Two solid spheres of same radius (R) and of same material are placed in such a way that their centres are 2R apart. The gravitational force between them is directly proportional to
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The state of stress acting at a critical point on a wrench is shown in the figure. P1 = 100 MPa and P2 = 270 MPa. P. Part A Determine the smallest yield stress for steel that might be selected for the part, based on the maximum shear stress theory. Express your answer to three significant figures and include appropriate units. PH M ?
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which of the following schedules would produce the longest pause after each reinforcement?
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A machine is supported on four steel springs for which damping can be neglected. The natural frequency of vertical vibration of the machine-spring system is 200 cycles per minute. The machine generates a vertical force p(t) = posinot. The amplitude of the resulting steady- state vertical displacement of the machine is to = 0.2 in. when the machine is running at 20 revolutions per minute (rpm), 1.042 in. at 180 rpm, and 0.0248 in. at 600 rpm. Calculate the amplitude of vertical motion of the machine if the steel springs are replaced by four rubber isolators that provide the same stiffness but introduce damping equivalent to 5 25% for the system. Comment on the effectiveness of the isolators at various machine speeds.
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a rapidly spinning paddle wheel raises the temperature of 200 ml of water from 21c to 25c. how much (a) heat is transferred and (b) work is done in this process?
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A 59.9g sample of brass, which has a specific heat capacity of 0.375Jg1C1, is put into a calorimeter (see sketch at right) that contains 150.0g of water. The temperature of the water starts off at 19.0C. When the temperature of the water stops changing it's 21.5C. The pressure remains constant at 1atm. Calculate the initial temperature of the brass sample. Be sure your answer is rounded to 2 significant digits.
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pretend you (80 kg) are making repairs on the outside of the international space station. you are floating 20 meters away from the space station when your safety rope comes loose. you throw your 10 kg tool-bag away from the space station in order to return to the station. if you are able to throw the bag at 5 m/s, how long does it take you to reach the station safely? a. 10 seconds b. 32 seconds c. 4 seconds d. 25 seconds
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Two substances at different temperatures are brought together and allowed to reach thermal equilibrium. Substance B has a specific heat capacity that is four times that of substance A. The mass of substance A is two times the mass of substance B.Which statement best describes the final temperature of the two substances after they are allowed to reach thermal equilibrium?A)The final temperature will be midway between the initial temperatures of the two substances.B)The final temperature will be closer to the initial temperature of substance B.C)The relative final temperature cannot be determined based on the information given.D)The final temperature will be closer to the initial temperature of substance A.
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An incompressible fluid is flowing through a vertical pipe with a constriction. The wide section is 2.00 cm in diameter and is at the top of the pipe. The pressure of the fluid in the wide section at the top is 200 kPa. The velocity of the fluid in the wide section is 4.00 m/s. The narrow section is located 8.00 m below the wide section. What is the diameter of the narrow section for the pressure of the fluid in the narrow section equal the pressure of the wide section? (density of the fluid is 680 kg/m^3)1.10 cm1.42 cm1.31 cm1.20 cm1.55 cm
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Two balls of equal mass, moving with & speed of 3.0 m/s, collide head on Find the velocity of each after impact for each of the following situations They have an inelastic (stick) collision. They have perfectly elastic collision (KE conserved)
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For a science project, you would like to horizontally suspend an 8.5 by 11 inch sheet of black paper in a vertical beam of light whose dimensions exactly match the paper.A) If the mass of the sheet is 1.0 g, what light intensity will you need?
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