In the diagram to the right, q = 1.5 μC, Q = 2.0 μC, r = 0.20 m, and the mass of the particle with charge Q is M = 5.0 g. a. Add to the diagram a useful coordinate system and forces acting on the charge Q. b. Find the magnitude and direction of the total electrostatic force on Q. c. Assuming only the electrostatic force is acting, what is the acceleration (magnitude and direction) of the charge Q?
A wire lying along a y axis from y = 0 to y = 0.309 m carries a current of 1.63 mA in the negative direction of the axis. The wire fully lies in a nonuniform magnetic field given by B→ = (0.251 T/m)yi^ + (0.226 T/m)yj^. What are the (a) x, (b) y, and (c) z components of the magnetic force on the wire? (a) Number Units (b) Number Units (c) Number Units
In the figure an electron is shot at an initial speed of v0 = 4.92×106 m/s, at angle θ0 = 38.2∘ from an x axis. It moves through a uniform electric field E→ = (4.69 N/C)j→. A screen for detecting electrons is positioned parallel to the y axis, at distance x = 3.22 m. What is the y component of the electron's velocity (sign included) when the electron hits the screen? Number Units
Only two horizontal forces act on a 4.1 kg body. One force is 9.1 N, acting due east, and the other is 1.5 N, acting 40∘ north of west. What is the magnitude of the body's acceleration? Number Units
In the figure an electron (e) is to be released from rest on the central axis of a uniformly charged disk of radius R. The surface charge density on the disk is +4.32 μC/m2. What is the magnitude of the electron's initial acceleration if it is released at a distance (a) R, (b) R/120, and (c) R/1320 from the center of the disk? (a) Number Units (b) Number Units (c) Number Units
The electronic flash attachment for a camera contains a capacitor for storing the energy used to produce the flash. In one such unit, the potential difference between the plates of an 850−μF capacitor is 320 V. (a) Determine the energy that is used to produce the flash in this unit. (b) Assuming that the flash lasts for 7.5 ms, find the effective power or "wattage" of the flash. (a) Number Units (b) Number Units
A charged cork ball of mass 1.70 g is suspended on a light string in the presence of a uniform electric field as shown in the figure below. When E→ = (1.40 ı^ + 5.40 j^)×105 N/C, the ball is in equilibrium at θ = 37.0∘. (i) (a) Find the charge on the ball. C (b) Find the tension in the string. N
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 man is standing beneath two rain clouds, equidistant from each cloud, as shown in the figure. Cloud A has an excess of 7.6×104 negative charges while cloud B has 7.6×104 positive charges (where a charge has magnitude e). (a) What is the magnitude of the net electric field where the man is standing? N/C (b) What is the direction of the net electric field where the man is standing? (Assume the +x-axis is to the right.) ∘ counterclockwise from the +x-axis
In the figure a thin glass rod forms a semicircle of radius r = 3.25 cm. Charge is uniformly distributed along the rod, with +q = 1.88 pC in the upper half and −q = −1.88 pC in the lower half. What is the magnitude of the electric field at P, the center of the semicircle? Number Units
A car is traveling along a straight road at a velocity of +38.8 m/s when its engine cuts out. For the next 1.10 seconds, the car slows down, and its average acceleration is a1. For the next 5.92 seconds, the car slows down further, and its average acceleration is a2. The velocity of the car at the end of the 7.02 -second period is +29.9 m/s. The ratio of the average acceleration values is a1 /a2 = 1.84. Find the velocity of the car at the end of the initial 1.10-second interval. Number Units