A free electron and a free proton have the same kinetic energy. This means that, compared to the matter wave associated with the proton, the matter wave associated with the electron has: a shorter wavelength and a greater frequency a longer wavelength and a greater frequency a shorter wavelength and the same frequency a longer wavelength and the same frequency a shorter wavelength and a smaller frequency
A particle of charge +3.6 μC is released from rest at the point x = 69 cm on an x axis. The particle begins to move due to the presence of a charge Q that remains fixed at the origin. What is the kinetic energy of the particle at the instant it has moved 15 cm if (a) Q = +29 μC and (b) Q = −29 μC? (a) Number Units (b) Number Units
A 2000- kg car is traveling with a speed of 10.4 m/s. What is the magnitude of the horizontal net force that is required to bring the car to a halt in a distance of 38.5 m? Number Units
A 3.0-kg ball and a 1.0-kg ball are placed at opposite ends of a mass-less beam so that the system is in equilibrium as shown. Note: The drawing is not drawn to scale. What is the value of the ratio of the lengths, b/a? 2.0 2.5 4.0 3.0 5.0
Multiple-Concept Example 13 presents useful background for this problem. The cheetah is one of the fastest accelerating animals, for it can go from rest to 33.6 m/s in 5.68 s. If its mass is 105 kg, determine the average power developed by the cheetah during the acceleration phase of its motion. Express your answer in (a) watts and (b) horsepower. (a) Number Units (b) Number Units
Suppose you design an apparatus in which a uniformly charged disk of radius R is to produce an electric field. The field magnitude is most important along the central perpendicular axis of the disk, at a point P at distance 2.30R from the disk (see Figure (a)). Cost analysis suggests that you switch to a ring of the same outer radius R but with inner radius R/2.30 (see Figure (b)). Assume that the ring will have the same surface charge density as the original disk. If you switch to the ring, by what part will you decrease the electric field magnitude at P? (a) (b) Number Units
A dart is thrown horizontally with an initial speed of 19 m/s toward point P, the bull's-eye on a dart board. It hits at point Q on the rim, vertically below P, 0.19 s later. (a) What is the distance PQ? (b) How far away from the dart board is the dart released? (a) Number Units (b) Number Units
Two large, parallel, conducting plates are 16 cm apart and have charges of equal magnitude and opposite sign on their facing surfaces. An electrostatic force of 5.3×10−15 N acts on an electron placed anywhere between the two plates. (Neglect fringing.) (a) Find the magnitude of the electric field at the position of the electron. (b) What is the magnitude of the potential difference in volts between the plates? (a) Number Units (b) Number Units
Multiple-Concept Example 13 presents useful background for this problem. The cheetah is one of the fastest accelerating animals, for it can go from rest to 33.6 m/s in 5.68 s. If its mass is 105 kg, determine the average power developed by the cheetah during the acceleration phase of its motion. Express your answer in (a) watts and (b) horsepower. (a) Number Units (b) Number Units
Three charged particles of q1 = 70.0 nC, q2 = −70.0 nC, and q3 = 35.0 nC are placed on the y-axis, as shown in the figure. Charge q1 has the coordinates (0, 12.0 cm), q2 has the coordinates (0, −12.0 cm), and q3 is located at the origin. (a)Find the electric potential energy (in J) of the configuration of the three fixed charges. (b)A fourth particle, with a mass of 1.74×10−13 kg and a charge of q4 = 140.0 nC, is released from rest at the point (9.00 cm, 0). Find its speed (in m/s) after it has moved freely to a very large distance away.
What capacitance is required to store an energy of 14 kW⋅h at a potential difference of 800 V? Number Units
A 2.03 kg book is placed on a flat desk. Suppose the coefficient of static friction between the book and the desk is 0.502 and the coefficient of kinetic friction is 0.273. How much force Fstart is needed to begin moving the book? Fstart = N How much force F is needed to keep the book moving at constant speed once it begins moving? F =
An infinite line of charge with charge per unit length λ1 = +8.00 μC/m is on the x-axis. A second very long line of charge with charge per unit length λ2 = −4.00 μC/m is parallel to the x-axis, at y = 15.0 cm. Part A At what point on the y-axis is the resultant electric field of the two lines of charge equal to zero? Enter the y coordinate of the point and include the appropriate units. View Available Hint(s) y0 = Value Units Submit