Four identical particles of mass 0.929 kg each are placed at the vertices of a 3.40 m x 3.40 m square and held there by four massless rods, which form the sides of the square. What is the rotational inertia of this rigid body about an axis that (a) passes through the midpoints of opposite sides and lies in the plane of the square, (b) passes through the midpoint of one of the sides and is perpendicular to the plane of the square, and (c) lies in the plane of the square and passes through two diagonally opposite particles?
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The archerfish uses a remarkable method for catching insects sitting on branches or leaves above the waterline. The fish rises to the surface and then shoots out a stream of water precisely aimed to knock the insect off its perch into the water, where the archerfish gobbles it up. Scientists have measured the speed of the water stream exiting the fish's mouth to be 3.7 m/s. An archerfish spots an insect sitting 21 cm above the waterline and a horizontal distance of 31 cm away. The fish aims its stream at an angle of 41 ∘ from the waterline. Determine the height above the waterline that the stream reaches at the horizontal position of the insect. DO NOT USE THE KINEMATIC EQUATIONS.
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Hello, I have this question that I have been trying to solve for days. I am always able to solve the first part of the question, but I am never able to get the second part. Please help me understand how to set up this problem so I am able to solve it!
Q: Let's revisit the banked curves from earlier to see another reason they are useful.We are building a road, and at one place we need to make a turn with a radius of 30m. The coefficient of static friction between rubber and the material we are using is 0.6.
Part A: Assuming that the road is flat through the turn, what is the maximum speed a car could have and safely navigate the turn without sliding off the road?
Part B: Instead of keeping the road flat, let's bank the turn a little bit, giving the road an angle of 20∘ above the horizontal. With the banked turn, what is the maximum speed a car could have and still make it around the turn without sliding?
The answer for part A is 13.3 m/s and the answer for part B is 19 m/s but I don't know how to get the answer for part B.
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It lies in a one-dimensional box that is 0.1nm long.
Find the following.
(1) Draw a diagram of the energy levels of electrons up to
n=4.
(2) Obtain the wavelengths of all photons that could be released
when electrons are transferred from n=4 to n=1.
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(Please note that I put this question up already and they got CD and it was wrong. This does not include that CD are wrong, there can be more right answers, one can be wrong, or both).
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A neutron collides elastically with a helium nucleus (at rest initially) whose mass is four times that of the neutron. The helium nucleus is observed to scatter at an angle θ2 = 52° from the neutron's initial direction. The neutron's initial speed is 52000·m/s.
Determine the angle at which the neutron scatters, θ1, measured from its initial direction:
What is the speed of the neutron after the collision?
What is the speed of the helium nucleus after the collision?
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A charge per unit length λ = +6.00 μC/m is uniformly distributed along the positive y-axis from y = 0 to y = +a = +0.500 m. A charge per unit length λ = -6.00 μC/m, is uniformly distributed along the negative y-axis from y = 0 to y = –a = -0.500 m. What is the magnitude of the electric field at a point on the x-axis a distance x = 0.431 m from the origin?
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If glider #2 is at rest and located halfway in between the photogates. What will the resultant motion be if glider #1 is moving to the right with a speed of 0.5 m/sec and they stick together when they collide?
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(a) How much work is done on the steam when 3.52 mol of water at 100°C boils and becomes 3.52 mol of steam at 100°C at 1.00 atm pressure? (Assume the latent heat of vaporization of water is 2.26 106 J/kg.) kJ
(b) Assume the steam to behave as an ideal gas. Determine the change in internal energy of the system of the water and steam as the water vaporizes. kJ
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A curve of radius 75 m is banked for a design speed of 100 km/h .
If the coefficient of static friction is 0.36 (wet pavement), at what range of speeds can a car safely make the curve? [Hint: Consider the direction of the friction force when the car goes too slow or too fast.]
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A horizontal pipe contains water at a pressure of 140 kPa flowing with a speed of 1.2 m/s . The pipe narrows to one-half its original diameter.
What is the speed of the water?
Express your answer using two significant figures.
What is the pressure of the water?
Express your answer using two significant figures.
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A raft is made of 11 logs lashed together. Each is 34.0 cm in diameter and has a length of 5.50 m. How many people (whole number) can the raft hold before they start getting their feet wet, assuming the average person has a mass of 69.0 kg? Do not neglect the weight of the logs. Assume the density of wood is 600 kg/m³
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As an aid in working this problem, consult Concept Simulation 26.3. A converging lens has a focal length of 87.00 cm. A 12.0 cm tall object is located 155.0 cm in front of this lens.
(a) What is the image distance? cm
(b) Is the image real or virtual?
real virtual?
(c) What is the image height? Be sure to include proper algebraic
sign.
cm?
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78. A commuter train travels between two downtown stations. Because the stations are only 1.00 km apart, the train never reaches its maximum possible cruising speed. During rush hour the engineer minimizes the time interval ?t1 between two stations by accelerating the rate a1 = 0.100 m/s2 for a time interval ?t1 and then immediately braking with acceleration a2 = ?0.500 m/s2 for a time interval ?t2. Find the minimum time interval ?tand the time interval ?t1.
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