Calculate the moment of inertia of a baseball bat for the following cases.
(a) Assume the bat is a wooden rod of uniform diameter and take the pivot point to be in the middle of the bat, at the end of the bat, and 5 cm from the end of the handle, where a batter who "chokes up" on the bat would place his hands. Hint: Consider the bat as two rods held together at the pivot point.
Estimate the mass of the bat.
kg
Estimate the length of the bat.
m
(i) in the middle of the bat (Use your estimate.)
kg
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Astronauts use a centrifuge to simulate the acceleration of a
rocket launch. The centrifuge takes 30.0 s to speed up from rest to
its top speed of 1 rotation every 1.10 s . The astronaut is
strapped into a seat 4.00 m from the axis.
Part A
What is the astronaut's tangential acceleration during the first 30.0 s ?
Express your answer with the appropriate units.
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A 3.60-kg block starts from rest at the top of a 30.0° incline and slides a distance of 2.30 m down the incline in 1.80 s.
(a) Find the magnitude of the acceleration of the block.
(b) Find the coefficient of kinetic friction between block and plane.
(c) Find the friction force acting on the block.
magnitude
direction
(d) Find the speed of the block after it has slid 2.30 m.
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Throughout history, research in the physical sciences has often been limited by our abilitiesof safely observing and studying the very phenomenon in question. As we make technological progress, we have increasingly more tools to expand our observational capabilities. Write a three to five (3-5) page paper in which you: Part 1: Procedures in the Physical Sciences: Challenges in Measurements Identify three (3) specific challenges to making direct measurements in the fields of astronomy, chemistry, physics, or earth science. Describe how scientists have utilized indirect forms of measure to overcome these challenges. Choose two (2) of the most historically influential tools or techniques in the physical sciences. Explain how these techniques or tools work, and how they helped to advance our understanding of the physical sciences. Part 2: Procedures in the Physical Sciences: A Survey of Safety Choose one (1) hazard associated with research in the physical sciences. Discuss how protective gear or equipment might be used to mitigate the hazard, as well as its efficacy. Describe the ways in which advancements in the physical sciences might impact the safety of the global community. Assess any special considerations for regulating this research. Part 3: Documentation Use at least four (4) quality resources in this assignment. Note: Wikipedia and similar Websites do not qualify as quality resources. The body of the paper must have in-text citations that correspond to the references. Integrate all sources into your paper using proper techniques of quoting, paraphrasing and summarizing, along with proper use of in-text citations to credit your sources.
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A converging lens (f = 11.7 cm) is located 26.6 cm to the left of a diverging lens (f = -5.42 cm). A postage stamp is placed 39.7 cm to the left of the converging lens. (a)Locate the final image of the stamp relative to the diverging lens. (b) Find the overall magnification.
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A -10nC charge is located at (x, y) = (0.80cm , 0 cm).
What is the x-component of the electric field at the position (x, y) = (5.2cm , 0 cm)?
What is the y-component of the electric field at the position (x, y) = (5.2cm , 0 cm)?
What is the x-component of the electric field at the position (x, y) = (?5.2cm, 0 cm)?
What is the x-component of the electric field at the position (x, y) = (?5.2cm, 0 cm)?
What is the x-component of the electric field at the position (x, y) = (0 cm, 5.2cm )?
What is the y-component of the electric field at the position (x, y) = (0 cm, 5.2cm )?
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250mL of water at 15.0 ?C is placed in the freezer compartment of a refrigerator with a coefficient of performance of 4.00. How much heat energy is exhausted into the room as the water is changed to ice at -20.0 ?C ?
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Why would it be silly to think of scientific reasoning in terms of deductive logic only? How could inductive logic give a better account of scientific reason
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You have been called to testify as an expert witness in a trial involving a head-on collision. Car A weighs 1515 lb and was traveling eastward. Car B weighs 1125 lb and was traveling westward at 42.0 mph. The cars locked bumpers and slid eastward with their wheels locked for 17.5 ft before stopping. You have measured the coefficient of kinetic friction between the tires and the pavement to be 0.750 . How fast (in miles per hour) was car A traveling just before the collision? (This problem uses English units because they would be used in a U.S. legal proceeding.)
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In a game of ultimate air hockey, pucks of different sizes and masses are used simultaneously. Angel has left her reach extended and Eric pounces on the opportunity by sending a puck of mass 2.0[kg] at a speed of 10.0[m/s] towards a puck of mass 5.0[kg] that is traveling at 5.0m/s] at an angle of 20.0o from the velocity of the first puck. After the collision, the 5.0[kg] puck has a speed of 6.0[m/s] in the original direction of the 2.0[kg] puck (to the right). What is the total, initial y-component of momentum in the system? Express your answer in kg*m/s.
A 20000 kg railroad car is rolling at 1.00 m/s when a 2000 kg load of gravel is suddenly dropped in.
What is the car's speed just after the gravel is loaded?
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Explain (quantitatively, not just words) why, given the efficiency of the heat pump (more calories of heat delivered than calories of work input to the heat pump), one can't take heat from the hot reservoir of the heat pump and make a perpetual motion machine by extracting enough energy to run the heat pump
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A proton flies horizontally towards a positively charged wall. It approaches the wall at a perfect zero degree angle and rebounds at the exact same speed in the opposite direction. Naturally the proton will never touch the wall. Apparently the kinetic energy in is conserved and the momentum is not, but how is that possible?
can you a) show me how this works algebraically and b) explain what is responsible for this?
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On a distant planet, golf is just as popular as it is on earth. A golfer tees off and drives the ball 2.7 times as far as he would have on earth, given the same initial velocities on both planets. The ball is launched at a speed of 41 m/s at an angle of 36° above the horizontal. When the ball lands, it is at the same level as the tee.
(a) On the distant planet, what is the maximum height of the ball?
(b) On the distant planet, what is the range of the ball?
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What is the moment of inertia of an object that rolls without slipping down a 2.42 m-high incline starting from rest, and has a final velocity of 6.56 m/s? Express the moment of inertia as a multiple of MR^2, where M is the mass of the object and R is its radius.
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A 2.90-kg hoop 1.50 m in diameter is rolling to the right without slipping on a horizontal floor at a steady 2.50 rad/s .
Part A
How fast is its center moving?
Express your answer with the appropriate units.
Part B
What is the total kinetic energy of the hoop?
Part C
Find the magnitude of the velocity vector of each of the following points, as viewed by a person at rest on the ground: (i) the highest point on the hoop; (ii) the lowest point on the hoop, (iii) a point on the right side of the hoop, midway between the top and the bottom.
Find the magnitude of the velocity vector for each of the points in part C, except as viewed by someone moving along with same velocity as the hoop.
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