An alien race passing through our solar system turns the Sun (1.98x1030 kg) into a black hole
using advanced gravity technology.
Determine the radius of the Sun if it were made into a black hole.
In 2-3 sentences, describe the effects on Earth and the rest of the solar system after the
Sun is converted to a black hole.
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A car is designed to get its energy from a rotating flywheel (solid disk) with a radius of 1.50 m and a mass of 600 kg. Before a trip, the flywheel is attached to an electric motor, which brings the flywheel's rotational speed up to 4,000rev/min.
(a) Find the kinetic energy stored in the flywheel.
(b) If the flywheel is to supply energy to the car as a 15.0-hp motor would, find the length of time the car could run before the flywheel would have to be brought back up to speed.
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(i) Explain the term half life. (ii) Explain how radioactive carbon dating works . (iii) The shroud of Turin is reputedly the burial garment used to wrap the body of Jesus 2000 years ago. A sample of the Shroud of Turin contains carbon 14 (C14). The half life of C14 is 5730 years and atmospheric C14 give 12 decays per minute per gram. An archaeologist measures an average decay rate from the shroud sample to be 1.5 decays per minute. Show by calculation whether this is consistent with the Shroud dating from the time of Jesus. (
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Which requires more work, lifting a 25 -kg load a vertical distance of 8.5 meters or lifting a 15-kg load a vertical distance of 17 m?
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A meter stick has a mass of 0.12 kg and balances at its center. When a small chain is suspended from one end, the balance point moves 29.0 cm toward the end with the chain. Determine the mass of the chain.
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I need new and unique answers, please. (Use your own words, don't copy and paste), Please Use your keyboard (Don't use handwriting) Thank you..
talk in 500-520 words about (shear wave elastography)
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Review Problem. Sir Lost-a-Lot dons his armor and sets out from the castle on his trusty steed in his quest to improve communication between damsels and dragons (Fig. P12.20). Unfortunately his squire lowered the draw bridge too far and finally stopped it 20.0° below the horizontal. Lost-a-Lot and his horse stop when their combined center of mass is 1.00 m from the end of the bridge. The uniform bridge is 9.50 m long and has a mass of 2400 kg. The lift cable is attached to the bridge 5.00 m from the hinge at the castle end, and to a point on the castle wall 12.0 m above the bridge. Lost-a-Lot's mass combined with his armor and steed is 950 kg. Suddenly, the lift cable breaks! The hinge between the castle wall and the bridge is frictionless, and the bridge swings freely until it is vertical. Figure P12.20
(a) Find the angular acceleration of the bridge once it starts to move. rad/s2 (
b) Find the angular speed of the bridge when it strikes the vertical castle wall below the hinge. rad/s2
(c) Find the force exerted by the hinge on the bridge immediately after the cable breaks. R = ( i + j) kN
(d) Find the force exerted by the hinge on the bridge immediately before it strikes the castle wall.
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1. How much work does the electric field do in moving a -8.6
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in an experiment, 60g of ice at -18C is mixed with 9g of steam at 130C (at 1 atm pressure). Neglecting any heat exchange with the surrounding.
(a)Determine the final state of the mixture.
(b) Determine the final temperature.
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1 (a). Examine. with practicals examples, the general form of a particle undergoing sinmple harmonic motion and carefully explain all the associated terms
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How does the ideal disposition of the four forces in an aircraft relate to the nose-up or nose-down pitching moments? What are the difficulties that the pilot can face to maintain such an ideal disposition for each of the forces while cruising?
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A satellite of mass 1,500 kg is placed in a circular Earth orbit at a height, h, above the surface. It is launched from Treasure Island in the SF Bay at 37 degrees latitude (north of the equator). 2465.98 10 , 6.37 10EarthEarthMxkgRx==ma) Derive Kepler’s Thrid Law from Newton’s Universal Law of gravity. b) If the orbital period of the satellite is 12 hrs, find the distance h above the Earth. c) What is the minimum energy required to put the satellite in orbit? Do not ignore the rotation of the Earth. d) What is the acceleration due to gravity at this height above the surface?p
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Rockets can be spin-stabilized; that is, they can fly straighter through space if they rotate around their long axis. Generally, 1 rotation per second is a good angular speed for spin-stabilization.
a. Assume the rocket acts like a solid cylinder. The rocket has a mass of 30000 kg (almost all of it fuel) and a radius of 1.00 m. Calculate the angular momentum of the rocket as it spins. Pay attention to units.
b. A problem arises because fuels for larger rockets are liquid. Due to the centripetal effect, the fuel is pushed to the outer skin of the rocket. So now the rocket acts more like a thin-walled hollow cylinder with a mass of 30000 kg and a radius of 1.00 m. Calculate the new angular velocity of this rocket, assuming that it is the same rocket as in part a. Describe what happened to the rocket’s spin.
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A parallel plate capacitor with plate separation d is connected
to a battery. The capacitor is fully charged to Q Coulombs and a
voltage of V. (C is the capacitance and U is the stored energy.)
Answer the following questions regarding the capacitor charged by a
battery. For each statement below, select True or False.
With the capacitor connected to the battery, increasing d
decreases Q.
After being disconnected from the battery, inserting a dielectric
with κ will increase V.
After being disconnected from the battery, inserting a dielectric
with κ will increase C.
With the capacitor connected to the battery, inserting a dielectric
with κ will decrease U.
With the capacitor connected to the battery, increasing d increases
U.
After being disconnected from the battery, decreasing d increases
C.
answers that have been wrong: FTTFTT, FFTFTT, TFTFTT, TFTFTF
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