Which term identifies a scalar quantity?
Two 20.-newton forces act concurrently on an object. What angle between these forces will produce a resultant force with the greatest magnitude?
The centripetal force acting on the space shuttle as it orbits Earth is equal to the shuttle’s
An 8.0-newton wooden block slides across a horizontal wooden floor at constant velocity. What is the magnitude of the force of kinetic friction between the block and the floor?
A particle could have a charge of
A rock is thrown straight up into the air. At the highest point of the rock’s path, the magnitude of the net force acting on the rock is
less than the magnitude of the rock’s weight, but greater than zero
greater than the magnitude of the rock’s weight
the same as the magnitude of the rock’s weight
An object accelerates uniformly from 3.0 meters per second east to 8.0 meters per second east in 2.0 seconds. What is the magnitude of the acceleration of the object?
As a box is pushed 30. meters across a horizontal floor by a constant horizontal force of 25 newtons, the kinetic energy of the box increases by 300. joules. How much total internal energy is produced during this process?
A baseball is thrown at an angle of 40.0° above the horizontal. The horizontal component of the baseball’s initial velocity is 12.0 meters per second. What is the magnitude of the ball’s initial velocity?
As shown in the diagram, an open box and its contents have a combined mass of 5.0 kilograms. A horizontal force of 15 newtons is required to push the box at a constant speed of 1.5 meters per second across a level surface. The inertia of the box and its contents increases if there is an increase in the
speed of the box
mass of the contents of the box
magnitude of the horizontal force applied to the box
coefficient of kinetic friction between the box and the level surface
A number of 1.0-newton horizontal forces are exerted on a block on a frictionless, horizontal surface. Which top-view diagram shows the forces producing the greatest magnitude of acceleration of the block?
A car uses its brakes to stop on a level road. During this process, there must be a conversion of kinetic energy into
gravitational potential energy
When a teacher shines light on a photocell attached to a fan, the blades of the fan turn. The brighter the light shone on the photocell, the faster the blades turn. Which energy conversion is illustrated by this demonstration?
light → thermal → mechanical
light → nuclear → thermal
light → electrical → mechanical
light → mechanical → chemical
Two electrons are separated by a distance of 3.00 × 10−6 meter. What are the magnitude and direction of the electrostatic forces each exerts on the other?
2.56 × 10^−17 N away from each other
2.56 × 10^−17 N towards each other
7.67 × 10^−23 N away from each other
7.67 × 10^−23 N towards each other
Moving a length of copper wire through a magnetic field may cause the wire to have a
potential difference across it
A sound wave traveling eastward through air causes the air molecules to
vibrate east and west
vibrate north and west
move eastward, only
move northward, only
Which particles are not affected by the strong force?
A photon is emitted as the electron in a hydrogen atom drops from the n = 5 energy level directly to the n = 3 energy level. What is the energy of the emitted photon?
In the diagram, a stationary source located at point S produces sound having a constant frequency of 512 hertz. Observer A, 50. meters to the left of S, hears a frequency of 512 hertz. Observer B, 100. meters to the right of S, hears a frequency lower than 512 hertz. Which statement best describes the motion of the observers?
Observer A is moving toward point S, and observer B is stationary.
Observer A is moving away from point S,and observer B is stationary.
Observer A is stationary, and observer B is moving toward point S.
Observer A is stationary, and observer B is moving away from point S.
Which graph represents the relationship between the magnitude of the gravitational force exerted by Earth on a spacecraft and the distance between the center of the spacecraft and center of Earth? [Assume constant mass for the spacecraft.]
The diagram represents a circuit consisting of two resistors connected to a source of potential difference. What is the current through the 20.-ohm resistor?
A ray of light ( f = 5.09 × 1014 Hz) travels through various substances. Which graph best represents the relationship between the absolute index of refraction of these substances and the corresponding speed of light in these substances?
A 4.0-kilogram object is accelerated at 3.0 meters per second^2 north by an unbalanced force. The same unbalanced force acting on a 2.0-kilogram object will accelerate this object toward the north at
When two point charges of magnitude q1 and q2 are separated by a distance, r, the magnitude of the electrostatic force between them is F. What would be the magnitude of the electrostatic force between point charges 2q1 and 4q2 when separated by a distance of 2r?
In a process called pair production, an energetic gamma ray is converted into an electron and a positron. It is not possible for a gamma ray to be converted into two electrons because
charge must be conserved
momentum must be conserved
mass-energy must be conserved
baryon number must be conserved
The diagram shows a series of wave fronts approaching an opening in a barrier. Point P is located on the opposite side of the barrier. The wave fronts reach point P as a result of
Which particle would produce a magnetic field?
a neutral particle moving in a straight line
a neutral particle moving in a circle
a stationary charged particle
a moving charged particle
Which diagram represents the electric field between two oppositely charged conducting spheres?