Bravo
what is the purpose of a crash-test dummy?
to monitor the forces that could be exerted on a human being during a vehicle collision
In inelastic collisions, the net change in kinetic energy of the system is a loss or gain?
loss
How would describe most collisions that occur?
elastic, partially elastic, or inelastic
partially elastic
The force that causes the motion of a rocket-like system is called
thrust
the motion of a rifle that results from a bullet fired that is felt in your shoulder
recoil
What is the purpose of a ballistic pendulum?
to measure the kinetic energy of a projectile (projectile energy)
When momentum is not conserved, what must be true?
external or nonconservative forces act on the system
A change in momentum is called the
impulse
If the momentum of a system is changed, what else can be assumed to have changed? assuming it isn't a rocket
velocity
Right hand rule: Down toward the ground
Do angular and linear momentum have the same units?
no, in angular momentum its kg*m2/s
linear momentum is kg*m/s
If a system consists of two objects colliding on a level surface, then what can be said of the system's mechanical potential energy before and after the collision?
it does not change
If the velocity of a moving object is doubled, how will that effect its momentum?
the momentum will be doubled
minimize, because F = Δp/Δt
The collision of a baseball hitting a bird on a pitch is an example of a ____ collision
partially elastic
In the motions of an object that explode, what quantity is not conserved?
Kinetic energy
In an inelastic collision, what quantity is not conserved?
kinetic energy
In an inelastic collision, what happens to the kinetic energy that is lost?
it is converted to other forms of energy (thermal, acoustic)
In an elastic collision, is the total kinetic energy of the system conserved?
yes
Which of Newton's laws explains why Recoil momentum and thrust exist?
Newton's third law of motion
What are the SI units for linear momentum?
kg*m/s
What is the momentum of a 15 kg pool ball as it is chucked by a physics student with a velocity of 6 m/s at his friend(?) to his right?
p = mv = 15(6) = 90 kg*m/s to the right (direction matters because it is a vector)
In a true elastic collision, are any nonconservative forces at work?
no, if the collision is elastic, only conservative forces are at work
If two different masses collide in one dimension, mass 1 moving and mass stationary, and the result has mass 1 bounce back and mass 2 move forward slowly, what is true of the relative size of the masses?
mass 1 is less than mass 2
what is the relationship between the linear and angular momentum vectors of a rotating body such as a wheel?
the vectors are perpendicular to each other and may not be equal