课程名称︰普通物理学甲上
课程性质︰大一必修
课程教师︰李庆德
开课学院：电资学院
开课系所︰电机工程学系
考试日期（年月日）︰2014/12/25
考试时限（分钟）：50分钟
试题 :
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General Physics A Quiz 2 ( December 25, 2014 )
1. A 160-N child sits on a light swing and is pulled back and held with a
horizontal force of 100 N. The magnitude of the tension force of each of the
two supporting ropes is:
(A) 60 N (B) 94 N (C) 120 N (D) 190 N (E) 260 N
2. A window washer attempts to lean a ladder against a frictionless wall. He
finds that the ladder slips on the ground when it is placed at an angle of
less than 75°to the ground but remains in place when the angle is greater
than 75°. The coefficient of static friction between the ladder and the
ground:
(A) is about 0.13
(B) is about 0.27
(C) is about 1.3
(D) depends on the mass of the ladder
(E) depends on the length of the ladder
3. Assume that Earth is in circular orbit around the Sun with kinetic energy
K and potential energy U, taken to be zero for infinite separation. Then,
the relationship between K and U is:
(A) K = U
(B) K = -U
(C) K = U/2
(D) K = -U/2
(E) dependent on the radius of the orbit
4. A projectile is fired straight upward from Earth's surface with a speed
that is half the escape speed. If R is the radius of Earth, the highest
altitude reached, measured from the surface, is:
(A) R/4 (B) R/3 (C) R/2 (D) R (E) 2R.
5. The orbit of a certain a satellite has a semi-major axis of 1.5 * 10^7 m
and an eccentricity of 0.20. Its perigee ( minimum distance from Earth )
and apogee ( maximum distance from Earth ) are respectively:
(A) 1.2 * 10^7 m, 1.8 * 10^7 m
(B) 3.0 * 10^6 m, 1.2 * 10^7 m
(C) 9.6 * 10^6 m, 1.0 * 10^7 m
(D) 1.0 * 10^7 m, 1.2 * 10^7 m
(E) 9.6 * 10^6 m, 1.8 * 10^7 m
6. The displacement of an object oscillating on a string is given by
X(t) = Xm cos(ωt + ψ), If the object is initially displaced in the
negative x direction and given a negative initial velocity, then the phase
constant ψ is between:
(A) 0 and π/2 radians
(B) π/2 and π radians
(C) π and 3π/2 radians
(D) 3π/2 and 2π radians
(E) none of the above (ψ is exactly 0, π/2, π, or 3π/2 radians)
7. A block attached to a spring undergoes simple harmonic motion on a
horizontal frictionless surface. Its total energy is 50 J. When the
displacement is half the amplitude, the kinetic energy is:
(A) zero (B) 12.5 J (C) 25 J (D) 37.5 J (E) 50 J
8. Three physical pendulums, with masses m1, m2 = 2m1, and m3 = 3m1, have the
same shape and size and are suspended at the same point. Rank them according
to their periods, from shortest to longest.
(A) 1, 2, 3
(B) 3, 2, 1
(C) 2, 3, 1
(D) 2, 1, 3
(E) All the above are the same
9. A stationary source S generates circular outgoing waves on a lake. The wave
speed is 5.0 m/s and the crest-to-crest distance is 2.0 m. A person in a
motor boat heads directly toward S at 3.0 m/s. To this person, the frequency
of these waves is:
(A) 1.0 Hz (B) 1.5 Hz (C) 2.0 Hz (D) 4.0 Hz (E) 8.0 Hz
10. Two pipes are each open at one end and closed at the other. Pipe A has
length L and pipe B has length 2L. Which harmonic of pipe B matches in
frequency the fundamental of pipe A?
(A) The fundamental
(B) The second
(C) The third
(D) The fourth
(E) There is none
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备注：
当时考试时间不足五十分钟，改为任选八题或取较高分之八题为主。