The smallest known blackhole is XTE J1650-500 in a binary system in the Milky Way. It’s mass is with just 3.8 times the mass of the sun. On the other hand, the most massive blackhole known is located in a super massive galaxy named Holm 15A, which is thought to have already formed from the collision of at least 8 smaller galaxies. The BH’s mass is 40 billion times that of the Sun. Calculate the Schwarzschild radius of both blackholes.
You have discovered a new galaxy and you think you have identified an Type II Cepheid star with a period of 30 days. You measure its brightness and with the Period-Luminosity function you calculate the distance to the galaxy d. However, you later find out that in fact the star you had identified is a Type I Cepheid. Is the galaxy further than, or, close to, us than we previously expected? By what factor should you multiply d to get the correct distance to the new galaxy?
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Could you measure the Earth's magnetic field (magnitude and direction) using the magnetic field sensor? If so, How? If not, why not?
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On a trip, you get stuck in slow traffic and have to drive 90.0 km at 30.0 km/hr. Then the traffic clears up, and you're able to drive another 90.0 km at 60.0 km/hr.
a) In the original description of the trip, why was your overall average speed lower than 45.0 km/hr, the mathematical average of 30.0 km/hr and 60.0 km/hr?
b) Determine the speed at which you'd have to have driven the second 90.0 km so that your overall average speed would have been 45.0 km/hr.
c) What are the largest and smallest possible average velocities for this trip, as originally described? What further information would allow you to determine where in this range your actual average velocity was? Explain in practical terms.
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A 16-cm-long, zero-resistance slide wire moves outward, on zero-resistance rails, at a steady speed of 11 m/sm/s in a 0.14 T magnetic field. On the opposite side, a 1.0 Ω carbon resistor completes the circuit by connecting the two rails. The mass of the resistor is 56 mg
Part A
What is the induced current in the circuit?
Express your answer using two significant figures.
Part B
How much force is needed to pull the wire at this speed?
Express your answer using two significant figures.
Part C
If the wire is pulled for 10 s, what is the temperature increase of the carbon? The specific heat of carbon is 710J/(kg⋅C∘).
Express your answer using two significant figures.
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A point charge q1q1q_1 = 4.35 nCnC is located on the x-axis at xxx = 2.10 mm , and a second point charge q2q2q_2 = -6.25 nCnC is on the y-axis at yyy = 1.00 mm .
a)
What is the total electric flux due to these two point charges through a spherical surface centered at the origin and with radius r1r1r_1 = 0.385 mm ?
b)
What is the total electric flux due to these two point charges through a spherical surface centered at the origin and with radius r2r2r_2 = 1.50 mm ?
c)What is the total electric flux due to these two point charges through a spherical surface centered at the origin and with radius r3r3r_3 = 2.80 mm ?
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The emitting antenna of a 100-kW radio station radiates equally in all directions.
Part A
What is the magnitude Emax 600 m from the antenna?
Express your answer to two significant digits and include the appropriate units.
Emax =
Part B
What is the magnitude Bmax 600 m from the antenna?
Express your answer to two significant digits and include the appropriate units.
Bmax =
Part C
For the distance of 600 m from the antenna, calculate the maximum potential difference caused between the ends of a receiving antenna that is 1.0 m long, assuming the antenna is aligned perfectly with the electric field of the radio wave.
Express your answer to two significant digits and include the appropriate units
V =
Part D
What is the magnitude Emax 50 km from the antenna?
Express your answer with the appropriate units.
Emax =
Part E
What is the magnitude Bmax 50 km from the antenna?
Express your answer with the appropriate units.
Bmax =
Part F
For the distance of 50 km from the antenna, calculate the maximum potential difference caused between the ends of a receiving antenna that is 1.0 m long, assuming the antenna is aligned perfectly with the electric field of the radio wave.
Express your answer with the appropriate units.
V =
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Using the definition of magnitude: m=-2.5log F + C derive the
relation for the distance modulus: m-M=5logd-5
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How much energy is required to change a 44.0-g ice cube from ice at -11.0
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Two large, flat metal plates are parallel to each other, a distance d apart. A charge of Q is placed on them and then they are electrically isolated. As a result, at the midpoint between the two plates the electric field has magnitude E. If the separation of the plates is then reduced to d/2 what is the magnitude of the electric field at the midpoint?
A) 2E
B) E/2
C) 0
D) 4E
E) E
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A light bulb is 3.00m3.00m from a wall. You are to use a concave mirror to project an image of the bulb on the wall, with the image 2.252.25 times the size of the object.
1. How far should the mirror be from the wall?
2. What should its radius of curvature be?
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1a) Without a commutator, an electric motor would A) not move at allB) go too fast and burn out C) not allow current to flow through it D) go back and forth instead of always rotating in the same direction E) stop after at most half a turn 1b.) two current loops are parallel to one another. the force between them is attractive: A) neverB) always C) when their currents are in the same direction (e.g., both are clockwise) D) when their currents are in opposite directions (e.g., one is clockwise, one is counter-clockwise) 1c) In the right hand rule for the B field at the center of a loop of current: A) The fingers curve in the direction of the B field, the thumb points in the direction of the current.B) The fingers curve in the direction of the current, the thumb is the direction of the B field. C) The middle finger points towards the center of the loop, the index finger points towards the B field, and the thumb point in the direction of the current. D) The middle finger points towards the B field, the index finger points towards the center of the loop, and the thumb point in the direction of the current. 1d) You are a distance R from the center of a loop of current and from a straight line of current (both have the same current). What can you say about the magnitude of the two B fields? A) The B field from the line is about 2 times stronger than the B field from the loopB) The two B fields are the same magnitude C) The B field from the line is about 3 times stronger than the B field from the loop D) The B field from the loop is about 3 times stronger than the B field from the line E) The B field from the loop is about 2 times stronger than the B field from the line 1e) An electromagnet with an iron core amplifies the magnetic field due to the magnet itself by: A) aligning the magnetic domains in the iron with the field of the electromagnetB) scrambling the magnetic domains in the iron using the electromagnet C) orienting the magnetic domains in the iron perpendicular to the field of the electromagnet 1f) A solenoid has a: A) Strong uniform B field inside, directed radially outwards from the solenoid, small B field outsideB) Strong uniform B field outside, directed along the axis of the solenoid, small B field inside C) Strong uniform B field inside, directed along the axis of the solenoid, small B field outside D) Strong uniform B field outside, directed radially outwards from the solenoid, small B field inside 1g)A magnetic dipole experiences no torque in a magnetic field: A) when the magnetic dipole moment is perpendicular to the B fieldB) when the B field is uniform C) when the magnetic dipole moment points in the direction of the B field |
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The acceleration of a bus is given by a(t) = at, where a =1.2m/s^3.
a) If the bus's velocity at time t = 1.0s is 5.0m/s, what is its velocity at time t = 2.0s ?
b) If the bus's position at time t= 1.0s is 6.0m, what is its position at time t = 2.0s?
c) Sketch ay -t, vy -t, and x -t graphs for the motion.
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Two identical point charges (q = +5.80 x 10-6 C) are fixed at
opposite corners of a square whose sides have a length of 0.320 m.
A test charge (q0 = -7.90 x 10-8 C), with a mass of 6.20 x 10-8 kg,
is released from rest at one of the corners of the square.
Determine the speed of the test charge when it reaches the center
of the square.
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Given 2 objects moving at some velocity v relative to one another, is it possible to determine whether they are moving or whether the space between them is expanding?
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A small block with mass 0.0475 kg slides in a vertical circle of radius 0.600 m on the inside of a circular track. During one of the revolutions of the block, when the block is at the bottom of its path, point A, the magnitude of the normal force exerted on the block by the track has magnitude 3.90 N . In this same revolution, when the block reaches the top of its path, point B, the magnitude of the normal force exerted on the block has magnitude 0.680 N .
How much work was done on the block by friction during the motion of the block from point AA to point BB?
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