physics quiz 1-20
A wire along the z-axis carries a current of 4.9 A in the +z direction of the force exerted on a 3.3 cm long length of this wire by a uniform magnetic field pointing in the -z direction having a magnitude of .43 T.
.07 N, -y direction
In the figure, a small particle of charge -1.9x10^-6 C and mass m= 3.1x10^-12 kg has speed v= 8.1x 10^3 m/s as it enters a region of the uniform magnetic field. The particle is initially traveling perpendicular tot eh magnetic field and is observed to travel in the semicircular path shown with the radius R=5.0 cm. Find the magnitude and direction of magnetic field in the region.
.26 T, into the paper
Three particle travel through a region of space where the magnetic field is out of the page, as shown in the figure. What are the signs of the charges of these three particles?
1 is negative, 2 is neutral, 3 is positive
A proton moving westward with a velocity of 5 km m/s enters a magnetic field of .2 T pointing northward. What are the magnitude and direction of the force that the magnetic field exerts on the proton?
1.6 x 10^16 N upwards
A particle carrying a charge of +e travels in a circular path of radius R in a uniform magnetic field. If instead, the particle carried a charge of +2e, the radius of the circular path and have been
2R
The magnetic field at a distance of 2 cm from a long straight current- carrying wire 4 ut. What is the magnetic field at a distance of 1 cm from this wire?
8 ut
Identical light bulbs can be attached to identical batteries in three different ways (A, bateryB, or C) as shown in the figure. The ranking (from lowest to highest) of the total power produced battery is
B, A ,C
James and John drive from an overhang into the lake below. James simply drops straight down from the edge. John takes a running start and jumps with an initial horizontal velocity of 25 m/s. Compare the time it takes each to reach the lake below if there is no air resistence.
James and John will reach the lake at the same time
A pilot drops a package from a plane flying horizontally at a constant speed. Neglecting air resistance, when the package hits the ground horizontally location the plane will
be directly over the package
A wire lying in the plane of the page carries a current toward the bottom of the page, as shown in the figure. What is the direction of the magnetic force it produces on an electron that is moving to the left directly toward the wire, as shown?
directly toward the bottom of the page
We observe that a moving charged particle experiences no magnetic force. From this, we can definitely conclude that
either no magnetic field exists or the particle is moving parallel to the field
A positive charge is moving to the right and experiences an upward magnetic force, as shown in the figure. In which direction must be magnetic field have a component? (right angle)
into page
Two long parallel wires are placed side-by-side on a horizontal table carry identical current straight toward you. From your point of view, the magnetic field at a point exactly between the two wires
is zero
A charge that is moving in a static uniform magnetic field
may experience a magnetic force, but its speed will not change
A rectangular coil, with corners, labeled ABCD, has lenghth L and width w. It is placed between the poles of a magnet, as shown in the figure. If there is a current I flowing through this coil in the direction shown, what is the direction of the force of the force acting on section AB of this coil?
perpendicular to and into the page
Suppose the car traveling to the west begins to slow down as it approaches a traffic light. Which of the following statements about its acceleration is correct?
the acceleration is towards the east
A ball is thrown horizontally from the top of a tower at the same instant that a stone is dropped vertically. Which object is traveling when it hits the level ground below if neither of them experienced any air resistance?
the ball
Two long parallel wires are placed side-by-side on a horizontal table. If the wires carry current in opposite directions
the wires push away from each other
Consider a deer that runs from point A to point B . The distance the deer runs can be greater than the multitude of its displacement, but the magnitude of the displacement can never be greater than the distnce it runs.
true
A proton is to orbit Earth at the equator using Earth's magnetic field to supply part of the necessary centripetal force. In what direction should the proton move?
westward
