Doubling the weight suspended vertically from a coil spring will result in a change in the displacement of the spring's lower end by what factor?
a. 0.50
b. 1.0
c. 2.0
d. 4.0
e. 0.25
[Ques. 2] Superconductors have been discussed as a means for electrical energy storage. Because they are resistanceless, a current once started in a loop would continue without loss. If a current of 1.0 104 A were started in a huge toroidal coil of radius 1.0 km and inductance 50 H, how much electrical energy (in kWh) could be stored?
a. 300 kWh
b. 480 kWh
c. 690 kWh
d. 840 kWh
[Ques. 3] A 0.400-kg object is attached to a spring with spring constant k = 10.0 N/m and moves with simple harmonic motion over a horizontal frictionless surface. At the instant that it is displaced from equilibrium by 0.0550 m, what is its acceleration?
a. 2 200 m/s2
b. 220 m/s2
c. 0.220 m/s2
d. 1.38 m/s2
e. 0.550 m/s2
[Ques. 4] A 14.0-V battery is connected in series with a switch, 5.0- resistor and coil. What energy is stored in the coil when the current is 2.8 A? The time constant is 4.8 104 s.
a. 9.4E3 J
b. 1.9E2 J
c. 6.7E3 J
d. 3.8E3 J
e. 1.2E3 J
[Ques. 5] A large spring requires a force of 130 N to compress it only 0.01 m. What is the spring constant of the spring?
a. 13 N/m
b. 13 000 N/m
c. 1.3 N/m
d. 130 N/m
e. 6 500 N/m
[Ques. 6] What is the stored energy in a 0.50-mH coil carrying a current of 5.0 A?
a. 1.3E2 J
b. 6.3E3 J
c. 2.5E3 J
d. 2.5E2 J
e. 1.0E2 J
[Ques. 7] The SI base units for the spring constant are which of the following?
a. Kg/s2
b. kg/m2
c. kg/s2
d. Kg/m2
[Ques. 8] How is the energy stored in a current-carrying inductor related to the current value, I?
a. directly proportional to I 2
b. directly proportional to I 1/2
c. directly proportional to I
d. inversely proportional to I
[Ques. 9] When one note is above another note by an octave, the frequency of the higher pitch note is double that of the lower pitch note. The word octave may make you think that there are 8 steps from the lower note to the one an octave above. But wait How many steps are there on a piano from middle C to the next C above? Each key is a step. If each next key is a step, how many are there? Middle C is a white (W) key and the next note above is a black (B) key. Starting at middle C on the piano the sequence of key we go through to get to high C, is BWBWWBWBWBWW, the last key being high C. Count em. That's 12 steps. If the multiplying factor of the frequency for the next step is the same for each step, what is that multiplying frequency? All you need is given in this problem statement.
a. 101/12 b. 121/8
c. 21/8 d. 21/12
[Ques. 10] How is the energy stored in a current-carrying inductor related to its self-inductance, L?
a. directly proportional to L2
b. directly proportional to L1/2
c. directly proportional to L
d. inversely proportional to L
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