ch.6 physics
1kg chunk of putty moving at 1 m/s collides w and sticks to a 5kg bowling ball initally at rest the bowling ball and puuttythen move with a momentum of
1 kg m/s
A 2 kg rifle that is suspended by strings fires a .01 kg bullet at 200m/s. THe recoil Velocity of the rifle is about
1 m/s
a bungee jumper attains a speed of 30 m/s just as the bungee cord begins to strechis 2 s while coming to a halt the jumpers average deceleration is about
1.5 g
two identical glides slide toward eachother on an air track. one moves at 1 m/s and the other at 2 m/s they collide stick and moves at
1/2 m/s
consider massive gliders that slide friction free along a horizontal air track. glider a has a mass of 1 kg a speed of 1 m/s and collides with glider b that has amass of 5 kg and its at rest. if they stick upon collision their speed after collision will be
1/6 m/s
a 5000 kg freight car moving at 2m/s collides w a 10000 kg freight car at rest they couple upon collision and move away at
2 m/s
the speed of a 4kg ball witha momentum of 12 kg m/s
3 m/s
the change in momentum that occurs when a 1 kg bal traveling at 4 m/s strikes a wall and bounces back at2 m/s
6 kg m/s
a cannon recoils while firing a cannonball. the speed of the cannons recoil is relatively smal because
a cannon has much more mass than the cannonball
as bronco brown steps off a hovering high flying helicopter and falls through the air he experiences
acceleration
as bronco brown steps off a hovering high flying helicopter and falls through the air he experiences
all of the above
the force dropped apple hitting the grund depends upon
all of the above
a red car has a head on collision with an approaching blue car with the same magnitude of momentum. a green car driving with the same momentum as the other cars collide with an enormously massive wall. which of the three cars will experence the greatest imulse
all the same
two vehicles with equal magnitude of momentum traveling at right angles to eachother undergo an inelastic collision. The combined wreck moves in a direction
at 45 degress to the direction of either car before collision
Youre driving down the highway and a bug splatters into your windshield which undergoes the greater change in momentumduring the time of contact
both the same
a karate chop is more effective if ones hand
bounce upon impact
it is correct to say the impulse is equal to
corresponding change in momentum
when bullets are fired from an airplane in the forward direction the momentum of the airplane is
decreased
an open freight car rolls friction free along a horizontal track in a pouring ran that falls vertically. as water accumulates in the car the cars speed
decreases
when freddy frog drops vertically from a treee onto a horizontally moving skateboard the speed of the skateboard
decreases
if all people animals trains trucks all over the world began to walk or run towards the east
earth would spin a bit slower
which has greater momentum when moving
either of these depending on speed
Elastic Collision
even though objects bounce off eachother their shape does not change
the force that accelerates a rocket in outerspace is exerted by the
exhausr gases
Momentum
final times time
two vehicles with equal magnitudes of momentum traveling at right angles to each other undergo an inelastic collision. Magnitude of momentum for the combined wreck is
greater than the magnitude of momentum of either car before collision
a softer landing occurs when a falling object bounces from a surface
in a extended time
a large heavy truck and a small baby carriage roll down a hill. neglecting friction at the bottom of the hill the baby carriage will likely have
less mmentum
if you cant avoid being hit by a fast moving object youll suffer a saller contact force if you can extend that force over a
longer time
impulse
mass times velocity
a golf ball moving forward with 1 unit of momentum strikes and bounces backward off a heavy boowling ball that is initally at rest and free to move. the bowling ball is set in motion with a momentum of
more than 1 unit
if severl balls are thrown straight up with different inital speeds the quantity that will have same value along their paths is their
move away from each othher but at different speeds
if a monkey floating in outespace throws his hat away the hat and the monkey will both
move away from eachother but at different speeds
an astronaut floating alone in outer spave throws a baseball if the ball moves away at 2o m/ s the astronaut will
move in opposite direction at lower speed
the conservation of momentum is most closely related to
newtons 3rd law
the impulse momentum relationship is a direct result oof
newtons third law
Law of conservation of momentum
no external forces and there is a consistent moment
a sandbag motionless in outer space is hit by a three time as massice sandbad moving at 12 m/s they stick together and move at a speed of
none of the above
a karate expert executes a swift blos and breaks a cement block with her bare head the magnitude of the force on her hand is
same as the force applied to the block
Inelastic
the shape does change even though objects do not bounce off of eachother
to catch a fast moving ball you extend your hand forward before contact with the ball and let it ride backward in the direction of the balls motion. doing this reduces the force of the contact on your hand principally because the
time of contact is increased
a frieght train rolls along a track with a considdrable momentum. if it rolls at the same speed but has twice as much mass its momentum is
twice