40 terms

# Physics B Final exam

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A -4.0-C charge is located 0.45 m to the left of a +6.0-C charge. What is the magnitude and direction of the electrostatic force on the positive charge?
1.1 N to the left
Complete the following statement: The magnitude of the electric field at a point in space does not depend upon
the sign of the charge causing the field
Which one of the following figures shows a qualitatively accurate sketch of the electric field lines in and around this system?
wide arrows going out
Two point charges are separated by 1.00 × 10-2 m. One charge is -2.8 × 10-8 C; and the other
is +2.8 × 10-8 C. The points A and B are located 2.5
× 10-3 m from the lower and upper point charges as shown
If an electron, which has a charge of 1.60 × 10-19 C, is moved from rest at A to rest at B, what is the change in electric potential energy of the electron?
-2.1 x 10^-14 J
Which one of the following changes will necessarily increase the capacitance of a capacitor?
placing a dielectric between the plates
At what distance from a 1.0-C charge is the electric potential equal to 12 V?
7.5 x 10^8 m
Which one of the following statements concerning resistors in series is true?
The current through each resistor is the same
A non-ideal battery has a 6.0-V emf and an internal resistance of 0.6 . Determine the
terminal voltage when the current drawn from the battery is 0.5 A.
5.7V
Which one of the following statements concerning capacitors of unequal capacitance
connected in series is true?
The total voltage supplied by the battery is the sum of the voltages across each capacitor
The figure shows a circuit. The switch S can be closed on either point A or C, but not both at the same time. Use the following quantities:
What is the equivalent resistance between the points A and B?
2 ohms
A charged particle is moving in a uniform, constant magnetic field. Which one of thefollowing statements concerning the magnetic force exerted on the particle is false?
The magnetic force increases the speed of the particle
An electron traveling horizontally enters a region where a uniform magnetic field is directed into the plane of the paper as shown. Which one of the following phrases most accurately describes the motion of the electron once it has entered the field?
Downward and circular
The figure shows two concentric metal loops, each carrying a current. The larger loop carries a current of 8.0 A and has a radius of 0.060 m. The smaller loop has a radius of 0.040 m. What is the value of a current in the smaller loop that will result in zero total magnetic field at the center of the system?
5.3 A
A long, straight wire is in the same plane as a rectangular, conducting loop. The wire carriesa constant current I as shown in the figure. Which one of the following statements is true if the wire is suddenly moved toward the loop?
There will be an induced current that is counterclockwise around the loop
A circular coil has 275 turns and a radius of 0.045 m. The coil is used as an ac generator by rotating it in a 0.500 T magnetic field, as shown in the figure. At what angular speed should the coil be rotated so that the maximum emf is 175 V?
A transformer changes 120 V across the primary to 1200 V across the secondary. If the secondary coil has 800 turns, how many turns does the primary coil have?
80
Which one of the following statements concerning electromagnetic waves is false?
X-rays have longer wavelengths than radio waves
A cellular telephone transmits electromagnetic waves at a frequency of 835 MHz. What is the wavelength of these waves?
.359 m
Unpolarized light of intensity S0 passes through two sheets of polarizing material whose transmission axes make an angle of 60° with each other as shown in the figure. What is the intensity of the transmitted beam, ST?
So/8
An electromagnetic wave has an electric field with a peak value of 250 N/C. What is the average intensity of the wave?
83 W/m²
Which one of the following statements is not a characteristic of a plane mirror?
The image is real
A concave mirror has a radius of curvature of 60.0 cm. How close to the mirror should an object be placed so that the rays travel parallel to each other after reflection?
30.0cm
An object is placed 20 cm in front of a concave spherical mirror that has a radius of curvature 60 cm. Which one of the following phrases best describes the image?
virtual and located 60cm from the mirror
The table lists the index of refraction for various substances at 20 °C for light with a wavelength of 589 nm in a vacuum. Through which substance will light with a vacuum wavelength of 589 nm travel with the greatest speed?
C ethyl alcohol
A 2.00-cm tall object is placed 40.0 cm from a lens. The resulting image is 8.00-cm tall and upright relative to the object. Determine the focal length of the lens.
53.3cm
A child sitting at the edge of a swimming pool sees a coin resting on the bottom of the pool.The coin appears to be 0.75 m directly below the water's surface. How deep is the pool at the location of the coin? The index of refraction of water is 1.33.
1.0 m
Two identical light waves, A and B, are emitted from different sources and meet at a point P. The distance from the source of A to the point P is LA; and the source of B is a distance LB from P. Which one of the following statements is necessarily true concerning the interference of the two waves?
A and B will interfere constructly if LA=LB
What is the minimum (non-zero) thickness of a benzene (n = 1.501) thin film that will result in constructive interference when viewed at normal incidence and illuminated with orange light (vacuum = 615 nm)? A glass slide (ng = 1.620) supports the thin film.
204 nm
Light with a wavelength of 644 nm uniformly illuminates a single slit. What is the width of the slit if the first-order dark fringe is located at = 0.125°?
2.95 x 10^-4 m
Visible light of wavelength 589 nm is incident on a diffraction grating that has 3500 lines/cm. At what angle with respect to the central maximum is the fifth order maximum observed?
A fifth order maximum cannot be observed
Complete the following statement: The Michelson-Morley experiment
indicated that the speed of light is the same in all inertial reference frames
A digital wireless telephone communicates to a base via microwaves with a frequency of 1930 MHz. What are the momentum and energy for the microwave photons emitted by the telephone? momentum photon energy
4.27x10^-33 kg m/s 1.28x10^-24J
The de Broglie wavelength of an electron (m = 9.11 × 10-31 kg) is 1.2 × 10-10 m. Determine the kinetic energy of the electron.
1.7x10^-17J
Name the physicist credited with the following statement: No two electrons in an atom can have the same set of values for the four quantum numbers.
Wolfgang Pauli
39. Consider the following list of electron configurations:
(1) 1s2 2s2 3s2 (4) 1s2 2s2 2p6 3s2 3p6 4s2
(2) 1s2 2s2 2p6 (5) 1s2 2s2 2p6 3s2 3p6 4s2 3d6
(3) 1s2 2s2 2p6 3s1
Which one of the above lists represents the electronic configuration for the ground state of the
atom with Z = 11?
3
An electron makes a transition from a higher energy state to a lower one without any external provocation. As a result of the transition, a photon is emitted and moves in a random direction.
What is the name of this emission process?
spontaneous emission
At what speed is a particle traveling if its kinetic energy is three times its rest energy?
.968c
Complete the following statement: The results of special relativity indicate that
Newtonian mechanics is a valid approx at low speeds (v<<c)
Upon which one of the following parameters does the energy of a photon depend?
frequency
Complete the following statement: An individual copper atom emits electromagnetic radiation with wavelengths that are
unique to all copper atoms