PHYS250L FINAL
The tension of a massless string is _____ the pulling force exerted on one end of the string. equal to greater than less than All of the above
equal to
Static friction
exists between two objects that are not moving relative to one-another even though an applied force acts to attempt to cause motion
the _____ determines the how many spaces the decimal moves in scientific notation.
exponent
Rigid bodies
extended objects with unchanging shapes that can be oriented in infinite ways relative to other objects. A ruler is an example
If an object starts at a positive position on the x-axis and undergoes a negative displacement, its final position must be negative. True False
false because either positive or negative, depending on the magnitude of the displacement
The velocity versus time graph can be constructed by determining the slope of the acceleration versus time graph at each time. True False
false because the velocity versus time graph can be constructed by determining the slope of the position or the area of the acceleration versus time graph at each time.
Spring potential energy is conserved for a hanging mass on a spring at rest. True False
false because total potential energy is conserved for a hanging mass on a spring at rest
spring constant
for a mass on a spring, the constant of proportionality, k
_____ are used to illustrate scientific data. Unknown variables Graphs Scientific notations All of the above
graphs
scatter plots
graphs in which points are plotted and the correlation, or relationship, among the points is analyzed
As the angle of incline of a ramp increases towards 90°, the acceleration of a marble down the ramp _____. increases decreases remains constant All of the above
increases
Friction between objects ______ the thermal energy of the molecules at the surface, resulting in an _______ in surface temperature.
increases increase
Velocity _____ when acceleration points in the _____ direction as the velocity. increases; same increases; opposite decreases; same None of the above
increases; same
why you should perform multiple trials with a meter stick
reduce the error, but will not increase the precision of the device.
A spring stretched beyond its elastic limit will _____. return to its original length remain deformed still follow Hooke's law None of the above
remain deformed
As the distance a marble travels down a ramp at a constant incline increases, the acceleration of the marble _____. increases decreases remains constant All of the above
remains constant
The quality of measurement data with high percent uncertainty but low percent error can be improved with _____. a correction factor device calibration repeated measurement trails All of the above
repeated measurement trails
y-axis
represents the dependent variable, or the variable that changes in response to the independent variable.
x-axis
represents the independent variable, the variable that is controlled or regulated by the investigator
A motion diagram
represents the position of an object at equally-spaced time intervals
drag
resistive force between a fluid (liquid or gas) and a passing solid object
friction
resistive force opposing motion between two objects in contact with one another. Always present any time two objects slide or attempt to slide against one another
pulley
simple machine consisting of a grooved wheel turning on an axle
static equilibrium
state of an extended object that is neither rotating nor changing position
The resistive force of drag occurs between a passing object and _____. air water molasses All of the Above
All of the Above
Typical Vernier calipers consist of a _____ for measuring small objects. depth probe pair of inner jaws pair of outer jaws All of the above
All of the Above
Springs combined in parallel will each experience the same _____. displacement force spring constant All of the above
All of the above
Static equilibrium occurs when the _____ is zero. net force net torque velocity All of the above
All of the above
The _____ influences the magnitude of the static friction force. normal force coefficient of static friction applied force All of the above
All of the above
The _____ is an example of a base unit of measurement associated with a physical object. meter kilogram second All of the above
All of the above
The _____ of a moving object is required when constructing a motion diagram. acceleration initial velocity initial position All of the above
All of the above
Torque can be found using the equation _____. τ=rF τ=r⊥F τ=rFsin(θ) All of the above
All of the above
elastic limit
Maximum stress that a material will withstand without permanent deformation.
A hockey puck sliding across frictionless ice is a good example of _____. Newton's first law Newton's second law Newton's third law
Newton's first law
free-fall
Objects that move with constant acceleration equal to the acceleration due to gravity, g = 9.8 m/s2
Accuracy is reported quantitatively as _______
Percent error
Random Error
Produced by device limitations resulting in both high and low measurements
Systemic eror
Produced by poorly calibrated devices resulting in consistently high or low measurements
Drag Coefficient (Cd)
Single value assigned to a set of standard approximate shapes
_____ velocity is the velocity of an object moving in a circular path in uniform circular motion. Tangential Centripetal Circular None of the above
Tangential
The restoring force is proportional to the displacement from the equilibrium. True False
True
Velocity and displacement vectors must always point in the same direction. True False
True
percent error
Used to quantify the difference between measured and expected values
If the net force is zero, then the _____ of the object will be zero. speed velocity acceleration All of the above
acceleration
centripetal acceleration
acceleration caused by the change in velocity from uniform circular motion always points towards the center of the circular path traveled by the object
Newton's third law of motion is directly related to _____. velocity and force action and reaction force and acceleration
action and reaction
Velocity
amount of distance travelled in a particular direction during a specific period of time vector which points in same direction as displacement
The angle of repose
angle at which an object rests on an inclined surface. The maximum angle of repose is the largest angle for which the object remains at rest. See Figure 7.
variable
any type of data, event, time period, or other category that is measured
center of mass
average position of all parts of the object or system weighted according to mass
line of action
axis along which force is applied
fixed pulley
stationary and will not move when a string or rope runs through it the rotation of the pulley itself does not need to be taken into account during calculations because it is "massless"
radial distance
distance between the pivot point and the point of application of the force.
The spring constant indicates the _____ of the spring. length mass stiffness None of the above
stiffness
The theoretical mechanical advantage is equal to the number of _____ supporting the load. pulleys string segments effort forces All of the above
string segments
Kinematics
study of how things move, without regard to the cause of the motion.
Improperly calibrated devices cause _____ error. precision random systematic All of the above
systematic
The _____ depends on the mass of the object. drag force acceleration due to gravity terminal velocity All of the Above
terminal velocity
displacement
the change in position of an object
torque
the force applied to an extended object multiplied by the perpendicular distance from the pivot point to the line of action of the force. Torque is measured in units of Newton-meters (N m)
restoring force
the force pulling the spring back toward equilibrium
Friction is caused by________
the interactions of microscopic molecules at the surface of two interacting objects
kinetic friction
Friction between moving surfaces
The density of an object can be used to determine its composition. True False
True
equation you would use for linear acceleration of an object on a ramp
a=g sinθ
uncertainty
range of values within which the true value lies
5.84 x 10^3 name the base
10
5.84 x 10^3 name the exponent
3
5.84 x 10^3 name the coefficient
5.84
Newton's first law of motion (law of inertia)
A body at rest tends to stay at rest, and a body in motion tends to stay in motion in a straight line, unless acted upon by a net force.
compound pulley system
A combination of fixed and movable pulleys
True Value
A known quantity that serves as a scientific reference.
scalar quantity
A physical measurement that does not contain directional information (distance and speed)
Newton's Second Law of Motion
Acceleration is directly proportional to the net force acting on an object and inversely proportional to the mass of the object.
The _____ of the object influences the drag force. shape cross-sectional area velocity All of the Above
All of the Above
_________ are the most commonly used graphs for scientific data
Bar graphs, scatter plots, and line graphs
terminal velocity
Constant reached when the drag force is equal to the force of gravity
Hooke's Law
F=-kx The equation for a restoring force Where, Fx = restoring force in the x-direction k = a constant of proportionality x = displacement from equilibrium.
The speed of an object moving in multiple directions is the same as the magnitude of the velocity. True False
False
The drag force increases the maximum height and maximum range traveled by a projectile. True False
False because The drag force decreases the maximum height and maximum range traveled by a projectile.
In a free-body diagram, all the forces acting on an object start with their head on the dot that represents the object. True False
False because all the forces acting on an object start with their tail on the dot
A car going around a curve at a constant speed of 40 mph does not experience acceleration. True False
False because experiences acceleration because of the change it its direction.
The force of static friction is always equal to the coefficient of static friction multiplied by the normal force. True False
False because the force of static friction is less than or equal to the coefficient of static friction multiplied by the normal force.
Random error can be eliminated by performing multiple measurements on an object. True False
False. it can be reduced but not fully eliminated
air resistance
Fluid friction acting on an object moving through the air
Newton's Third Law of Motion
For every action, there is an equal and opposite reaction.
pivot point
The axis around which the extended object rotates
The force of friction always acts parallel to the surface of interaction. True False
True
The magnitude of the velocity at time t is determined by calculating the area under the acceleration versus time graph and adding the initial velocity. True False
True
_____ is the rotational equivalent of force and causes rotational motion. Center of mass Moment of inertia Torque All of the above
Torque
A force applied at a 90° angle to the moment arm produces the largest possible torque. True False
True
All measurements of physical quantities are subject to errors and uncertainties True False
True
Multiple trials should be conducted when measuring objects with Vernier calipers in order to reduce random error. True False
True
Random error results in measurements with unpredictable high and low values. True False
True
The centripetal force always points in the same direction as the centripetal acceleration. True False
True
Fd=1/2CdρAv^2
Where: Fd=drag force (N) Cd=object drag coefficient ρ=medium density (kg/m3) A=object cross-sectional area (m2) v=object velocity (m/s)
Vernier caliper
a precision instrument consisting of a main scale containing one jaw and Vernier scale containing a second jaw that slides along the main scale
vector quantity
a quantity that has both magnitude and direction (acceleration, displacement, and velocity)
Static friction is caused by molecular _____ and kinetic friction is caused by molecular _____. attraction; bonds attraction; repulsion bonds; attraction None of the above
bonds; attraction
Volume
calculated value of the space an object occupies
The term centripetal means _____. circular center-seeking towards the margin None of the above
center-seeking
label a vernier caliper
clockwise starting at top left Inner jaws, main scale, depth probe, vernier scale, outer jaws
Scientific notation is a method of writing long numbers in a(n) _____ format. condensed expanded unregulated All of the above
condensed
An object moving as a projectile experiences a _____ drag. constant constantly changing constantly increasing None of the Above
constantly changing
Dimensional analysis is a problem-solving technique used for _____. writing scientific notation converting units determining graph axes All of the above
converting units
Free-body diagrams
depict all the forces acting on an object, using arrows to represent magnitude and direction
Accuracy
describes how close a measured value is to the true value
Multiple pulleys used together in a system can be used to change the _____ of the applied force. magnitude direction direction and magnitude None of the above
direction and magnitude
The friction force is _____ proportional to the normal force on an object. inversely directly quadradically None of the above
directly
speed
distance (as opposed to displacement) travelled divided by the elapsed time
Divisions of a vernier scale
indicate the least count, or smallest quantity that the instrument can measure. For most Vernier calipers, the least count will range between 0.1 mm (about the thickness of a sheet of paper) and 0.05 mm (about the size of the smallest cells in the human body).
The goal of solving an equation is to ________
isolate the unknown variable
zero error on vernier calliper
jaws are closed and the alignment of the "0" mark on both the Vernier scale and main scale is noted
For a machine with a mechanical advantage greater than one, the distance over which the input force acts is _____ the distance over which the output force acts. larger than smaller than equal to None of the above
larger than
The force of kinetic friction for a particular pair of interacting objects is always _____ the force of static friction. less than greater than equal to None of the above
less than
For moving objects with speeds less than a few hundred meters per second, drag increases _____ the velocity. like the square root of like the like the square of None of the Above
like the square of
The moment of inertia depends on how the _____ of an object is distributed. gravity inertia mass All of the above
mass
Inertia
measure of a body's resistance to change its state of movement. Inertia has a direct relationship with mass
work
measure of energy, measured in units of joules (J) and is defined as the force multiplied by the distance over which the force acts where: W=F×d W=work F= force d =distance over which the force acts
outer jaws
measure the exterior diameters and lengths of objects
depth probe
measures interior depths and lengths of hollow or tubular objects like a soda can
inner jaws
measures the inside diameter between two surfaces
Inertia is a body's resistance to _____. force of mass gravity deceleration motion changes
motion changes
Acceleration is directly proportional to the _____ of an object. velocity net force speed mass
net force
When the drag force reaches the magnitude of the accelerating force the object _____. no longer accelerates speeds up slows down None of the Above
no longer accelerates
the main point of Newton's first law
no net force acting on object = constant velocity if velocity = 0 then object is at rest If the velocity = nonzero the object maintains the velocity and travels in a straight line.
Uniform circular motion
occurs when objects travel in a circular path at a constant speed, while their direction of velocity changes.
Drag points in the _____ the motion of a solid moving object. same direction as opposite direction of perpendicular direction to None of the Above
opposite direction of
Precision is reported quantitatively as _______
percent uncertainty
The velocity of an object at time t can be determined from the slope of the _____ versus time graph at that time. position acceleration velocity None of the above
position
dimensional analysis
problem-solving technique used for converting units
tension
pulling force exerted by a string or rope
force
push or pull on an object, represented by a vector with magnitude and direction
Numerical data is also called __________-
quantitative data
efficiency
the ratio of actual mechanical advantage to theoretical mechanical advantage, expressed as a percentage
Mechanical Advantage
the ratio of output force to the input force: MA=Fout/Fin out force being the load and input force being the applied force
Density
the ratio of the mass of an object to the volume it occupies intrinsic property that does not vary with the amount of a substance being measured (ρ=mV)
Acceleration
the time rate of change of the velocity and is a vector quantity measured in units of (m/s)/s or m/s2
law of conservation of energy
the total energy within an isolated system is constant
The dots in motion diagrams are always equally spaced in _____. space time space and time None of the above
time
Newton's second law can be demonstrated by a(n) _____. soccer ball on the grass inflated balloon truck turning a curve at a constant speed of 15 mph man leaning against a wall
truck turning a curve at a constant speed of 15 mph
. A displacement is positive if it points up or to the right in the Cartesian coordinate system. True False
true
In free fall, acceleration is constant. True False
true
The coefficient of static friction for a certain pair of materials is greater than the coefficient of kinetic friction for the same pair of materials. True False
true
derived units
units assigned to these calculated measurements (force, velocity, density_
equilibrium position of a spring
unstretched length
line graph
used to illustrate data points that are dependent upon one another
Acceleration is the time rate of change of the _____ of a moving object. position displacement velocity None of the above
velocity
tangential velocity
velocity of the object as it moves in the circular path in uniform circular motion. The tangential velocity is always tangent to the circular path at each point in the object's motion
v=v0+atv=v0+at relates _____ and _____. position; time position; velocity velocity; time velocity; acceleration
velocity; time
The change in spring potential energy of a spring is equal to the amount of _____ on the spring. work done weight mass All of the above
work done