Transcript mc_oscillations

A sled on ice moves with friction so small that it can be ignored.
A person wearing spiked shoes standing on the ice exerts a
force to the sled. The sled is moving toward the left. Which
force would slow it down at a steady rate?
A
The force is toward the right and is increasing in magnitude.
B
The force is toward the right and is of constant magnitude.
C
The force is toward the left and is increasing in magnitude.
D The force is toward the left and is of constant magnitude.
E
The force is toward the left and is decreasing in magnitude.
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1
A piece of wire is stretched by a certain amount and allowed to
return to its original length. It is then stretched twice as far
(without exceeding the elastic limit). Compared to the first
stretching, the second elongation stored
A
B
C
D
E
twice as much energy
four times as much
half as much
the same amount
none of these.
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2
Simple harmonic motion (SHM) is a technical term used to describe a
certain kind of idealised oscillation. Practically all the oscillations that one
can see directly in the natural world are much more complicated than
SHM. Why then do physicists make such a big deal out of studying SHM?
A
It is the only kind of oscillation that can be described
mathematically.
B
Any real oscillation can be analysed as a superposition (sum
or integral) of SHMs with different frequencies.
C
Physics is concerned mainly with the unnatural world.
D
To make it easy for students.
E
It is good torture for students.
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Simple harmonic motion (SHM) is a technical term used
to describe a certain kind of idealised oscillation.
A simple harmonic oscillation has
A
fixed frequency and fixed amplitude.
B
fixed frequency and variable amplitude.
C
variable frequency and fixed amplitude.
D
variable frequency and variable amplitude.
E
fixed frequency and fixed wavelength.
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4
Which of the following statements is true of the acceleration of
a particle oscillating with SHM?
A
It is always in the opposite direction to the velocity of
the particle.
B
It varies linearly with the frequency of oscillation.
C
It has the smallest magnitude when the speed of the particle
is greatest.
D
It decreases as the potential energy increases.
E
It magnitude is a minimum when the displacement of the
particle is a maximum.
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5
A point on a string vibrating sinsusoidally is now at one extreme
position. If it takes 2 s for it to move to the other extreme
position, what is the period of the wave?
A
1s
B
2s
C
4s
D
8s
E
16 s
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6
A simple harmonic oscillation of a given system can be specified
completely by stating its
A
amplitude, frequency and initial phase.
B
amplitude, frequency and wavelength.
C
frequency and wavelength.
D
frequency, wavelength and initial phase.
E
amplitude, frequency, phase.
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7
We can't get very far in talking about SHM without doing a little
mathematics, so it its important to be able to recognise some
equations which can represent SHM. Only one of the following
equations does not represent SHM. Which one is that?
A
y  A sin( t )
B
y  B cos( t )
C
y  A sin( t )  B cos( t )
D
y  A sin( t   )
E
y  A sin( t )  B cos(2 t )
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8
Here is a displacement-time graph of an object moving with
simple harmonic motion. What is the frequency of the SHM?
A
B
C
D
E
0.40 Hz
1.25 Hz
2.50 Hz
5.00 Hz
0.20 Hz
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9
Here is a displacement-time graph of an object moving with
simple harmonic motion. What is the amplitude of the SHM?
A
B
C
D
E
2.5 cm
4.0 cm
5.0 cm
8.0 cm
10 cm
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10
Here is a displacement-time graph of an object which is not
moving with simple harmonic motion. But it is still an oscillation
and it has a period. What is the period?
A
B
C
D
E
0.25 s
0.5 s
0.75 s
1.0 s
2.0 s
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Consider a block hanging from a spring. The system is set vibrating by
pulling the block down below its equilibrium position and then letting it
go from rest. The frequency of the oscillation is determined by
A
B
C
D
E
the amount of the initial displacement
the mass of the block and the properties of the spring
the local gravitational field, g
all of the above
the mass of the block,the properties of the spring and g.
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12
The system was set vibrating by pulling the block down below its
equilibrium position and then letting it go from rest. If the initial
displacement is doubled what happens to the maximum kinetic
energy of the block?
A
B
C
D
E
It is unchanged.
It is doubled.
It is increased by a factor of 4.
We can't tell from the information provided.
It is halved.
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Think about whether
these two systems are
significantly different in
other respects and decide
which one of the
following statements is
true.
A
The systems have different periods because their motions are aligned differently with
the gravitational field.
B
The hanging system has a slightly smaller period because the weight of the spring has
to be accounted for.
C
The hanging system has a slightly larger period because the weight of the spring has to
be accounted for.
D
E
The two systems have identical periods, no matter what the weight of the spring.
Don't know.
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