Question : 71.Fraud in science rare because it difficult to commit. Why : 1777251

71.Fraud in science is rare because it is difficult to commit. Why is it difficult to commit fraud in science?
A.Science requires that experimental and theoretical findings be reproducible.
B.All scientists are bound by a code of ethics preventing them from publishing fraudulent work.
C.Scientific results are reviewed by other scientists before they are published.
D.Scientific journals only allow certain highly trusted individuals to publish their work.
E.a and c above

72.As material flows into a black hole
A.the material will experience time dilation.
B.the material will become hotter.
C.the material will produce an absorption spectrum.
D.the material will appear to us to fall into the black hole very rapidly.
E.a and b

73.The first pulsar was discovered by __________ in November of 1967.
A.Jocelyn Bell
B.Isaac Newton
C.Albert Einstein
D.Walter Baade
E.Edwin Hubble

74.A pulsar requires that a neutron star

I.	rotate rapidly.
II.	have a radius of at least 10 km.
III.	have a strong magnetic field.
IV.	rotate on an axis that is different from the axis of the magnetic field.

A.I & III
B.I & IV
C.II, III, & IV
D.I, III, & IV
E.I, II, III, & IV

75.None of the pulsars emit pulses of visible light because
A.pulsars are to hot to emit visible light.
B.pulsars contain black holes that won't let visible light escape.
C.the gravitational field of a pulsar is so great that the visible light emitted is red shifted.
D.pulsars are too far away for the visible light to be bright enough to be detected at Earth.
E.A few pulsars do emit visible light pulses.

76.Millisecond pulsars that are very old are
A.believed to be the result of mass transfer from a companion that increases the spin of the pulsar.
B.all single objects.
C.not spinning as rapidly they seem because they have four hot spots that produce the flashes.
D.X-ray binaries.
E.gamma-ray bursters.

77.The Schwarzschild radius of a 1 black hole is approximately
A.3 km.
B.1,500,000 km, the size of the Sun
C.150,000,000 km or 1 AU.
D.3 ´ 10¹³ km or 1 pc.

78.The escape velocity of an object depends on

I.	the mass of that object.
II.	the mass of the object trying to escape.
III.	the distance from the center of the object and the escaping object.
IV.	the speed of light.

A.I, II, III, & IV
B.I & II
C.I & III
D.I, II, & IV
E.I, III, & IV

79.If the inner accretion disk around a black hole has a temperature of 10⁶ K, at what wavelength will it radiate the most energy? Hint: wavelength in nm =3,000,000/T in K
A.10⁶ nm
B.3 nm
C.3 ´ 10⁶ nm
D.1 nm
E.3 ´ 10¹¹ nm

80.The singularity of a black hole
A.is found outside the event horizon.
B.is located within the event horizon.
C.can only be located if the black hole is in a binary system.
D.doesn't exist since all black holes have a finite size.

81.The escape velocity at the event horizon around a black hole is
A.smaller than the speed of light.
B.equal to the speed of light.
C.much larger than the speed of light.
D.irrelevant since nothing (including light) can escape from a black hole.

82.Which of the following can you never know about a black hole?
A.Mass
B.Rotation
C.Electrical charge
D.The elements of the material that has fallen in.