The big 5 kinematic equations - CORRECT ANSWER-see image
missing a, d, v, Vo, and t respectively (adv vot)
slope of velocity vs time graph gives... - CORRECT ANSWER-acceleration
area under velocity vs time graph gives.. - CORRECT ANSWER-displacement
Newton's law of gravitation - CORRECT ANSWER-Every object in the universe exerts a
gravitational pull. Magnitude of this is proportional of the objects' masses and inversely
proportional to the square of the distance between them.
Fgrav = G(Mm/r^2)
This also = mg, as mg represents gravitational force.
The radius of Earth is approx 6.4 x 10^6 m. What is the mass? what equation is used? -
CORRECT ANSWER-g = GM/r^2
M is calculated to be 6 x 10^24
1000 N crate being pushed with 250 N of force. coefficient of static friction is 0.4. What
is Ff? - CORRECT ANSWER-It is not 400N (this would be the maximum frictional
force). Since it is only being pushed at 250, Ff is only 250 (imagine being pushed back
with 400 N of force when trying to push a box with 250 N!)
Force acting parallel to an inclined plane is... - CORRECT ANSWER-(mg)sin(theta)
Force acting perpendicular to an inclined plane is - CORRECT ANSWER-
mg(cos(theta))
Center of mass for point masses equation - CORRECT ANSWER-See image. x
represents locations of all the objects contributing to the center of mass relative to any
given reference point. Imagine a bunch of masses hanging from strings on a meter
stick. A question would ask "at what point would the meter stick have to be held to be
horizontal, given hanging masses at 20 cm (x1), 50 cm (x2) and 78 cm (x3)?" If the
meter stick itself has a mass (and center of mass), this has to be included as well. In
order to do so, you would multiply mass of meter stick by location of center of mass (M
x 50 cm) on the numerator, and you would incorporate the mass in the denominator just
like the other masses.
,See page 112 if confused.
Center of gravity equation - CORRECT ANSWER-See image. W is weight, x is location
of each mass relative to some chosen reference. If gravity is constant, this equation
becomes the same as center of mass.
Where is the acceleration of an object undergoing uniform circular motion pointing? -
CORRECT ANSWER-toward the center of the circle.
Uniform circular motion - CORRECT ANSWER-An object moving in a circular path, if its
speed is constant.
Magnitude of centripetal acceleration equation. - CORRECT ANSWER-See image.
Magnitude of centripetal force equation - CORRECT ANSWER-See image.
Fc = MAc = (MV^2)/r
Torque equation - CORRECT ANSWER-see image
Can also be written as tau = lF, with l being the lever arm.
lever arm - CORRECT ANSWER-shortest distance from pivot point to the line of action
of force. (the shortest distance is perpendicular to the line of action of force).
Translational equilibrium - CORRECT ANSWER-When net forces on an object are
equal to 0.
Rotational equilibrium - CORRECT ANSWER-When net torques on an object cancel.
How does moment of inertia relate to torque (formula) - CORRECT ANSWER-tau = Ia
Which has a greater rotational inertia (AKA moment of inertia)? a bar with weights in the
middle of it or on either end? - CORRECT ANSWER-Weights on the end (meaning it is
harder to rotate).
What would have a greater rotational inertia (moment of inertia)? a hollow ball or a solid
ball with the same mass? - CORRECT ANSWER-The hollow ball, as the mass is farther
from the axis of rotation. Important that they are the same mass.
What does theta represent in torque equation? (tau = fdsin(theta)) - CORRECT
ANSWER-It is the angle between r and F.
Primary work equation - CORRECT ANSWER-W = fdcos(theta)
, Theta represents angle between F and d!!!!
Primary power equation - CORRECT ANSWER-P = w/t
Primary kinetic energy equation - CORRECT ANSWER-KE = 1/2mv^2
Measures the amount of work done (in joules).
How to calculate work of a system if the kinetic energy is changing? - CORRECT
ANSWER-W = delta KE.
Work done by a force that's perpendicular to an object's motion is... - CORRECT
ANSWER-0. An example of this is centripital force. This does not do work on an object,
as an object in uniform circular motion is traveling perpendicular to its centripital force.
Change in potential energy with respect to gravity - CORRECT ANSWER-Delta PE =
negative work done by gravity = -mgh
Delta PE = +mgh if height is increased, -mgh is height is decreased.
The work done by gravity depends on.... - CORRECT ANSWER-only the initial and final
heights of the object, not on the path the object follows.
AKA, it is a conservative force!!
Is friction a conservative force? - CORRECT ANSWER-No, it depends on the path
taken!
Total mechanical energy = - CORRECT ANSWER-KE + PE
Look at example 6-23 on page 169... - CORRECT ANSWER-Notice that the initial angle
does not matter when doing a conservation of energy problem. THIS IS IMPORTANT!!!
I KNOW IT DOESN"T SEEM LIKE THIS IS RIGHT AT FIRST GLANCE!
Conservation of energy equation when another force is involved. It is no longer simply
KEi + PEi = KEf + PEf, as energy is not totally conserved! - CORRECT ANSWER-KEi +
PEi + work done by outside force = KEf + PEf
Mechanical advantage - CORRECT ANSWER-resistance force/effort force (or F out/F
in)
Resistance force is force that would be required without the help of a machine, and
effort force is the amount of force required by the machine.
Efficiency (%) - CORRECT ANSWER-Work output/energy input
missing a, d, v, Vo, and t respectively (adv vot)
slope of velocity vs time graph gives... - CORRECT ANSWER-acceleration
area under velocity vs time graph gives.. - CORRECT ANSWER-displacement
Newton's law of gravitation - CORRECT ANSWER-Every object in the universe exerts a
gravitational pull. Magnitude of this is proportional of the objects' masses and inversely
proportional to the square of the distance between them.
Fgrav = G(Mm/r^2)
This also = mg, as mg represents gravitational force.
The radius of Earth is approx 6.4 x 10^6 m. What is the mass? what equation is used? -
CORRECT ANSWER-g = GM/r^2
M is calculated to be 6 x 10^24
1000 N crate being pushed with 250 N of force. coefficient of static friction is 0.4. What
is Ff? - CORRECT ANSWER-It is not 400N (this would be the maximum frictional
force). Since it is only being pushed at 250, Ff is only 250 (imagine being pushed back
with 400 N of force when trying to push a box with 250 N!)
Force acting parallel to an inclined plane is... - CORRECT ANSWER-(mg)sin(theta)
Force acting perpendicular to an inclined plane is - CORRECT ANSWER-
mg(cos(theta))
Center of mass for point masses equation - CORRECT ANSWER-See image. x
represents locations of all the objects contributing to the center of mass relative to any
given reference point. Imagine a bunch of masses hanging from strings on a meter
stick. A question would ask "at what point would the meter stick have to be held to be
horizontal, given hanging masses at 20 cm (x1), 50 cm (x2) and 78 cm (x3)?" If the
meter stick itself has a mass (and center of mass), this has to be included as well. In
order to do so, you would multiply mass of meter stick by location of center of mass (M
x 50 cm) on the numerator, and you would incorporate the mass in the denominator just
like the other masses.
,See page 112 if confused.
Center of gravity equation - CORRECT ANSWER-See image. W is weight, x is location
of each mass relative to some chosen reference. If gravity is constant, this equation
becomes the same as center of mass.
Where is the acceleration of an object undergoing uniform circular motion pointing? -
CORRECT ANSWER-toward the center of the circle.
Uniform circular motion - CORRECT ANSWER-An object moving in a circular path, if its
speed is constant.
Magnitude of centripetal acceleration equation. - CORRECT ANSWER-See image.
Magnitude of centripetal force equation - CORRECT ANSWER-See image.
Fc = MAc = (MV^2)/r
Torque equation - CORRECT ANSWER-see image
Can also be written as tau = lF, with l being the lever arm.
lever arm - CORRECT ANSWER-shortest distance from pivot point to the line of action
of force. (the shortest distance is perpendicular to the line of action of force).
Translational equilibrium - CORRECT ANSWER-When net forces on an object are
equal to 0.
Rotational equilibrium - CORRECT ANSWER-When net torques on an object cancel.
How does moment of inertia relate to torque (formula) - CORRECT ANSWER-tau = Ia
Which has a greater rotational inertia (AKA moment of inertia)? a bar with weights in the
middle of it or on either end? - CORRECT ANSWER-Weights on the end (meaning it is
harder to rotate).
What would have a greater rotational inertia (moment of inertia)? a hollow ball or a solid
ball with the same mass? - CORRECT ANSWER-The hollow ball, as the mass is farther
from the axis of rotation. Important that they are the same mass.
What does theta represent in torque equation? (tau = fdsin(theta)) - CORRECT
ANSWER-It is the angle between r and F.
Primary work equation - CORRECT ANSWER-W = fdcos(theta)
, Theta represents angle between F and d!!!!
Primary power equation - CORRECT ANSWER-P = w/t
Primary kinetic energy equation - CORRECT ANSWER-KE = 1/2mv^2
Measures the amount of work done (in joules).
How to calculate work of a system if the kinetic energy is changing? - CORRECT
ANSWER-W = delta KE.
Work done by a force that's perpendicular to an object's motion is... - CORRECT
ANSWER-0. An example of this is centripital force. This does not do work on an object,
as an object in uniform circular motion is traveling perpendicular to its centripital force.
Change in potential energy with respect to gravity - CORRECT ANSWER-Delta PE =
negative work done by gravity = -mgh
Delta PE = +mgh if height is increased, -mgh is height is decreased.
The work done by gravity depends on.... - CORRECT ANSWER-only the initial and final
heights of the object, not on the path the object follows.
AKA, it is a conservative force!!
Is friction a conservative force? - CORRECT ANSWER-No, it depends on the path
taken!
Total mechanical energy = - CORRECT ANSWER-KE + PE
Look at example 6-23 on page 169... - CORRECT ANSWER-Notice that the initial angle
does not matter when doing a conservation of energy problem. THIS IS IMPORTANT!!!
I KNOW IT DOESN"T SEEM LIKE THIS IS RIGHT AT FIRST GLANCE!
Conservation of energy equation when another force is involved. It is no longer simply
KEi + PEi = KEf + PEf, as energy is not totally conserved! - CORRECT ANSWER-KEi +
PEi + work done by outside force = KEf + PEf
Mechanical advantage - CORRECT ANSWER-resistance force/effort force (or F out/F
in)
Resistance force is force that would be required without the help of a machine, and
effort force is the amount of force required by the machine.
Efficiency (%) - CORRECT ANSWER-Work output/energy input
