Physics MC

Which of the following is NOT considered to be one of the “fundamental forces”?

A. gravity
B. strong nuclear
C. friction
D. electromagnetic
E. weak nuclear

Which of the following forces is NOT associated with the “electromagnetic force”?
A. air resistance
B. gravity
C. friction
D. buoyancy
E. tension

When analyzing dynamics problems, free-body diagrams
A. are more useful when analyzing horizontal forces than when analyzing vertical forces
B. should be used only when objects are accelerating
C. should always be used
D. only apply to objects in equilibrium
E. should include only the forces that are directly responsible for the acceleration

An object is pushed horizontally at a constant velocity. What can correctly be said about the forces acting on the object?
A. The sum of all forces has a value directed forward.
B. The sum of all forces is zero.
C. The force(s) acting forward is/are greater than the force(s) acting backward.
D. The forces acting on the object can be said to be “unbalanced.”
E. Newton’s second law best summarizes the effect of the forces acting on the object.

Which of the following is NOT an example of “inertia”?
A. A person’s head jerks back as the car he is riding in accelerates forward.
B. A person’s head jerks forward as the car he is riding in suddenly stops.
C. A person is pressed up against the car door as the car turns a corner.
D. A person is largely unaware of a car’s motion when his eyes are closed.
E. All of the above are examples of inertia.

An object’s “weight”
A. depends on its mass
B. depends on the gravitational field strength
C. is properly measured in “newtons”
D. is equivalent to the force of gravity acting on the object
E. all of the above

With respect to Newton’s third law, the action and reaction forces
A. are equal provided the object is moving with uniform motion
B. act on different objects
C. are equal provided the object is at rest
D. are equal provided the object is NOT at rest or moving with uniform motion
E. being equal, imply a “balanced” force situation

According to Newton’s third law, when you walk across a floor, the force that propels you forward is
A. exerted upward by the floor on your feet (i.e., the normal force)
B. the force applied by your feet on the floor
C. the force of friction of your feet on the floor
D. the force of the floor applied against your feet
E. the force acting on you working against gravity

A 4.0-kg object, A, and a 2.0-kg object, B, are connected with a rope. A force is applied to another rope attached to the 2.0-kg object that pulls both A and B along a horizontal surface. Which of the following statements is true?
A. The sum of the applied force and the force that B exerts on A is equal to the force that A exerts on B.
B. The force that B exerts on A is equal to the force that A exerts on B provided that the system slides with uniform motion.
C. The force that B exerts on A is greater than the force that A exerts on B.
D. The force that A exerts on B is greater than the force that B exerts on A.
E. The force that B exerts on A is equal to the force that A exerts on B regardless of the motion of the system.

An object sits at rest on a ramp. As the angle of inclination of the ramp increases, the object suddenly begins to slide. Which of the following explanations best accounts for the object’s movement?
A. The component of gravity along the ramp has increased sufficiently.
B. The force of gravity acting on the object has increased sufficiently.
C. The friction has decreased sufficiently while the normal force has remained unchanged.
D. The coefficient of static friction has decreased sufficiently.
E. The normal force has increased sufficiently.

Streamlining is a technique that designers use to
A. decrease turbulent flow and increase laminar flow
B. increase turbulent flow and increase laminar flow
C. stop turbulent flow and stop laminar flow
D. increase turbulent flow and decrease laminar flow
E. decrease turbulent flow and decrease laminar flow

Which of the following does NOT utilize Bernoulli’s principle?
A. the lift force achieved by an airplane wing
B. the motion of a curve ball
C. the “spoiler” on the rear of an automobile
D. a Venturi “flowmeter”
E. All of the above utilize Bernoulli’s principle.

Which of the following would be considered an “inertial” frame of reference?
A. a moving escalator
B. a car moving through a turn at a constant speed
C. an object in “free fall”
D. a car pulling away as a traffic light turns green
E. all of the above

Which of the following frames of reference (inertial or noninertial) should NOT be grouped with the rest?
A. a child on a merry-go-round
B. a person standing on a moving escalator
C. a parachutist in “free fall”
D. a baseball as it is being hit by a bat
E. a satellite in Earth’s orbit

Imagine that you are travelling in a train and you have a drink sitting on the dining table in front of you. The train suddenly stops and the drink ends up in your lap. What force acting on the drink is responsible for its sudden motion?
A. the force of the table acting on the drink
B. the force of the drink on itself
C. the force of the wheels on the track
D. the force of the track on the wheels
E. There is no force acting on the drink that is responsible for its motion.

The law of inertia holds
A. only for inertial frames of reference
B. only for noninertial frames of reference
C. for all frames of reference, both inertial and noninertial
D. only in a gravitational field
E. only for objects travelling with uniform motion

For an object travelling with “uniform circular motion,”
A. its acceleration is always directed tangent to the circle
B. its velocity is always directed toward the centre of the circle
C. its velocity is constant
D. its speed and distance from the centre of the circle are constant
E. its speed may change provided the radius of the circle is constant

For an object travelling with “uniform circular motion,” its acceleration is
A. directed outward from the centre of the circle
B. zero because the speed is constant
C. changing in magnitude depending on its position in the circle
D. directed toward the centre of the circle
E. directed tangent to the circle

The reason that curves on roads are often banked is because
A. the coefficient of kinetic friction is increased
B. the normal force acting on the car is reduced
C. the coefficient of static friction is increased
D. the gravitational force acting on the car is reduced
E. a component of the normal force can contribute to the centripetal force

A rock is tied to the end of a string and whirled around in a circle that describes a vertical plane. At which position is the tension in the string the least?
A. The tension in the string is the same at all places on the circle.
B. on the descending side of the circle
C. at the top of the circle
D. at the bottom of the circle
E. on the ascending side of the circle

Imagine you are a passenger upside-down at the top of a vertical looping roller coaster. The centripetal force acting on you at this position
A. is perhaps the least of anywhere in the loop
B. is supplied at least partly by gravity
C. is supplied partly by the seat of the roller coaster
D. is directed vertically downward
E. all of the above

For objects travelling with uniform circular motion, the centrifugal force they experience
A. is radially outward
B. is apparently present in the noninertial frame of reference
C. increases with speed
D. doesn’t actually exist
E. all of the above

The person responsible for determining the value of the universal gravitational constant is
A. Isaac Newton
B. Galileo Galilei
C. William Herschel
D. Henry Cavendish
E. Albert Einstein

The orbital radius of a satellite circling the Earth
A. depends only on its orbital speed
B. depends only on its mass
C. depends on both its orbital speed and its mass
D. is the same for all satellites
E. is directly proportional to its orbital speed

Astronauts on board an orbiting space station appear to be “floating” because
A. they are outside Earth’s gravitational influence
B. they have become truly “weightless”
C. they are in the vacuum of space
D. they are in free fall along with the space station itself
E. the force of gravity acting on them has been reduced to an insignificant level

To produce an artificial gravity on board a space station
A. is purely science fiction
B. would require an enormous quantity of matter
C. would be possible by maintaining an inertial frame of reference
D. is easily achieved by rotating the space station
E. would be impossible