Question: Find the electric flux through the surface
Find the electric flux through the surface in Figure 15.28. Assume all charges in the shaded area are inside the surface.
(a) -(3 C)/є0
(b) (3 C)/є0
(c) 0
(d) -(6 C)/є0
Figure 15.28:
> Objects A and B with TA > TB are placed in thermal contact and come to equilibrium. (a) For which object does the entropy increase? (b) For which object does the entropy decrease? (c) Which object has the greater magnitude of entropy change?
> Objects A and B have the same size and shape with emissivities eA and eB and temperatures TA and TB, respectively. (a) If eA = eB and TB = 4TA, what is the ratio PB /PA of their radiated powers? (b) If, instead, they radiate the same power and eA = 4eB,
> The first law of thermodynamics is ΔU = Q + W. For each of the following cases, state whether the internal energy of an ideal gas increases, decreases, or remains constant: (a) No energy is transferred to the gas as it expands to twice its original volum
> In a calorimetry experiment, three samples A, B, and C with TA > TB > TC are placed in thermal contact. When the samples have reached thermal equilibrium at a common temperature T, which one of the following must be true? (a) QA > QB > QC (b) QA < 0, QB
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> The U.S. penny is now made of copper-coated zinc. Can a calorimetric experiment be devised to test for the metal content in a collection of pennies? If so, describe the procedure.
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> Different amounts of thermal energy are added to each of three isolated samples A, B, and C of lead. If the energy transfers are ordered as QB > QC > QA and each sample undergoes the same temperature change, which sample has the largest mass?
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> Calculate the slopes for the A, C, and E portions of Figure 11.3. Rank the slopes from least to greatest and explain what your ranking means. (a) A, C, E (b) C, A, E (c) E, A, C (d) E, C, A Figure 11.3:
> Suppose you have 1 kg each of iron, glass, and water, and all three samples are at 10°C. (a) Rank the samples from lowest to highest temperature after 100 J of energy is added to each by heat. (b) Rank them from least to greatest amount of energy transfe
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> If the light-bulbs in Quick Quiz 18.7 are connected one by one in series instead of in parallel, what happens to (a) The brightness of the light-bulbs? (b) The individual currents in the light-bulbs? (c) The power delivered by the battery? (d) The lifeti
> A 60.0-kg runner expends 3.00 x 102 W of power while running a marathon. Assuming 10.0% of the energy is delivered to the muscle tissue and that the excess energy is removed from the body primarily by sweating, determine the volume of bodily fluid (assum
> Suppose you have three identical light-bulbs, some wire, and a battery. You connect one light-bulb to the battery and take note of its brightness. You add a second light-bulb, connecting it in parallel with the previous light-bulbs, and again take note o
> When the switch is open in Figure 18.8, power Po is delivered to the resistor R1. When the switch is closed, which of the following is true about the power Pc delivered to R1? (Neglect the internal resistance of the battery.) (a) Pc (b) Pc = Po (c) Pc &g
> In Figure 18.8, the current is measured with the ammeter on the right side of the circuit diagram. When the switch is closed, does the reading on the ammeter (a) Increase, (b) Decrease, or (c) Remain the same? Figure 18.8:
> The circuit in Figure 18.5 consists of two resistors, a switch, an ammeter, and a battery. When the switch is closed, power Pc is delivered to resistor R1. When the switch is opened, which of the following statements is true about the power Po delivered
> In Figure 18.5, the current is measured with the ammeter at the bottom of the circuit. When the switch is opened, does the reading on the ammeter (a) Increase, (b) Decrease, or (c) Not change? Figure 18.5:
> Why does a battery get warm while in use?
> True or False: While discharging, the terminal voltage of a battery can never be greater than the emf of the battery.
> Two resistors, A and B, are connected in a series circuit with a battery. The resistance of A is twice that of B. Which resistor dissipates more power? (a) Resistor A does. (b) Resistor B does. (c) More information is needed.
> For the two resistors shown in Figure 17.12, rank the currents at points a through f from largest to smallest. (a) Ia = Ib > Ie = If > Ic = Id (b) Ia = Ib > Ic = Id > Ie = If (c) Ie = If > Ic = Id > Ia = Ib Figure 17.12:
> A voltage DV is applied across the ends of a Nichrome heater wire having a cross-sectional area A and length L. The same voltage is applied across the ends of a second Nichrome heater wire having a cross-sectional area A and length 2L. Which wire gets ho
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> All electric devices are required to have identifying plates that specify their electrical characteristics. The plate on a certain steam iron states that the iron carries a current of 6.00 A when connected to a source of 1.20 x 102 V. What is the resista
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> Look at the four “circuits” shown in Figure 17.6 and select those that will light the bulb. Figure 17.6:
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> A parallel-plate capacitor is disconnected from a battery, and the plates are pulled a small distance farther apart. Do the following quantities increase, decrease, or stay the same? (a) C (b) Q (c) E between the plates (d) ΔV (e) PEC
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> An electron initially at rest accelerates through a potential difference of 1 V, gaining kinetic energy KEe, whereas a proton, also initially at rest, accelerates through a potential difference of -1 V, gaining kinetic energy KEp. Which of the following
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> A spherical balloon contains a positively charged particle at its center. As the balloon is inflated to a larger volume while the charged particle remains at the center, which of the following are true? (a) The electric potential at the surface of the ba
> Consider a collection of charges in a given region and suppose all other charges are distant and have a negligible effect. Further, the electric potential is taken to be zero at infinity. If the electric potential at a given point in the region is zero,
> If a negatively charged particle is placed at point B in Figure 16.3 and given a very small kick to the right, what will its subsequent motion be? Will it (a) Go to the right and not return, (b) Go to the left, (c) Remain at point B, or (d) Oscillate aro
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> Consider a parallel-plate capacitor with a dielectric material between the plates. If the temperature of the dielectric increases, does the capacitance (a) Decrease, (b) Increase, or (c) Remain the same?
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> Suppose the electric field of Quick Quiz 15.7 is tilted 60° away from the positive z - direction. Calculate the magnitude of the flux through the same area. (a) 0 (b) 10.0 N · m2/C (c) 20.0 N · m2/C (d) More information is needed Electric Field in Quick
> A 40.-g block of ice is cooled to -78°C and is then added to 560 g of water in an 80.-g copper calorimeter at a temperature of 25°C. Determine the final temperature of the system consisting of the ice, water, and calorimeter. (If not all the ice melts, d
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> You are tuning a guitar by comparing the sound of the string with that of a standard tuning fork. You notice a beat frequency of 5 Hz when both sounds are present. As you tighten the guitar string, the beat frequency rises steadily to 8 Hz. To tune the s
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> As an airplane flying with constant velocity moves from a cold air mass into a warm air mass, does the Mach number (a) Increase, (b) Decrease, or (c) Remain the same?
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> Suppose you are throwing two dice in a friendly game of craps. For any given throw, the two numbers that are faceup can have a sum of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12. Which outcome is most probable? Which is least probable?
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> By visual inspection, order the PV diagrams shown in Figure 12.5 from the most negative work done on the system to the most positive work done on the system. (a) a, b, c, d (b) a, c, b, d (c) d, b, c, a (d) d, a, c, b Figure 12.5:
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