What must be true in Newton's second law if the object in question moves at a constant velocity? Similarly, what must be true in Newton's second law if the object accelerates? What are the customary rules for drawing a free body diagram? What is the value of drawing an a free body diagram? If 2 objects are in constant with each other. what does Newton's third law dictate should be evident when free body diagrams are drawn of the 2 objects?
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An electrostatic precipitator is to be designed to collect dust from a pulverized coal boiler with an actual flow of 100 m3/s. The effective migration velocity for the flyash is anticipated to be 0.08 m/s. The design gas flow velocity is 1.2 m/s, the plate height is 10 m, and the plate-toplate spacing (2s) is 0.25 m.
a. Determine the number of ducts required to accommodate the flow [-].
b. For an efficiency of 99%, determine the required plate length [m].
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A 3.4 μC charge is placed at the origin of coordinates, and a -2.6 μC charge is placed to the x axis at 2.5 cm .
Find the location of the place(s) along the x axis where the electric field due to these two charges is zero.
Find the location of the place(s) along the x axis where the electric potential due to these two charges is zero.
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Calculate the magnitude of the electric field at the center of a square with sides 20.5 cm long if the corners, taken in rotation, have charges of 1.18 μC, 2.36 μC, 3.54 μC, and 4.72 μC (all positive).
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A wheel, starting from rest, has a constant angular acceleration of 0.7 rad/s^2. In a 0.5-s interval, it turns through an angle of 101 rad. How long has the wheel been in motion at the start of this 0.5-s interval?
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An ancient club is found that contains 180 g of pure carbon and has an activity of 5.5 decays per second. Determine its age assuming that in living trees the ratio of (14C12C)(14C12C) atoms is about 1.40×10−121.40×10−12. Note that the half life of carbon-14 is 5700 years and the Avogadro number is 6.02×10236.02×1023.
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11. Can a 12 cm telescope distinguish two stars that are 1.5 arcseconds away from each other? Justify your answer numerically. (You can assume we're using light in the middle of the visual band.)
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A rigid tank contains 71.0 g of chlorine gas (Cl2) at a temperature of 70°C and an absolute pressure of 5.20 × 105 Pa. Later, the temperature of the tank has dropped to 37°C and, due to a leak, the pressure has dropped to 3.50 × 105 Pa. How many grams of chlorine gas have leaked out of the tank? (The mass per mole of Cl2 is 70.9 g/mol.)
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A 14.7 μF capacitor is charged to a potential of 55.0 V and then discharged through a 75.0 Ω resistor.
(a) How long after discharge begins does it take for the capacitor to lose 90.0% of the following?
(i) its initial charge: _______s
(ii) its initial energy: _______s
(b) What is the current through the resistor at both times in part
(a)?
(i) at tcharge: ________A
(ii) at tenergy: ________A
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(a) Compute the impedance of a series R-L-C circuit at angular
frequencies of w1 = 1000 rad/s, w2 = 735 rad/s and w3 = 540 rad/s.
Take =160 ohm, = 0.940 H and = 2.05 uF.
(b) Describe how the current amplitude varies as the angular
frequency of the source is slowly reduced from 1000 to 540 .
a-Amplitude is always constant.
b-Amplitude decreases.
c-Amplitude increases.
d-First amplitude increases next it decreases.
e-First amplitude decreases next it increases.
(c) What is the phase angle of the source voltage with respect to
the current when w = 1000 rad/s?
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A passenger on a moving train walks at a speed of 1.40 m/s due north relative to the train. The passenger's speed with respect to the ground is 4.5 m/s at an angle of 30.0° west of north. What are the magnitude and direction of the velocity of the train relative to the ground?
| magnitude | ___ m/s |
| direction | ____ ° west of north |
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A point charge +q is at the origin. A spherical Gaussian surface centered at the origin encloses +q. So does a cubical surface centered at the origin and with edges parallel to the axes. Select "True" or "False" for each statement below.
1. Suppose (for this statement only), that q is moved from the origin but is still within both the surfaces. The flux through both surfaces is changed.
2.If the radius of the spherical Gaussian Surface is varied, the flux through it also varies.
3. The area vector and the E-Field vector point in the same direction for all points on the spherical surface.
4. The E-Field at all points on the spherical surface is equal due to spherical symmetry.
5. The Electric Flux through the spherical surface is less than that through the cubical surface.
I tried :( F , T, F, T, F) but it is wrong, and I don't know which one is wrong.
I tried：
F T F T F
T F F T F
Both are wrong, and i dont know which one is wrong.
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what is myopia and hyperopia? How can we correct these?
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Two astronauts, Hans and Dexter, are on a spacewalk floating at
rest next to their space vehicle. They argue and Hans shoots Dexter
with a handgun. The bullet has a mass of 0.015 kg and a muzzle
velocity of 250 m/s. Hans now finds himself drifting away from the
spacecraft
a.) Hans and his spacesuit have a mass of 200 kg. how fast is he drifting away
b.) Hans only had one bullet, but he is holding a gun that has a mass of 1.1 kg. how fast must he throw it to stop drifting away from the spacecraft?
c.) Meanwhile, on earth, a solid cylinder of mass 5kg rolls without slipping toward a hill with a velocity of 5 m/s. how high up the hill will the cylinder roll?
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