physics test 4
what are to way to increase impulse?
by increasing magnitude of the applied external force and the time that the force acts on the system the system's momentum will change
how to find impulse
force x time
impulse
impulse = change in momentum= force x time = mas x velocity
When you are in the way of a fast-moving object and can't get out of its way, you will suffer a smaller force of impact if you decrease its momentum over a short or long time ?
longer time
conversation of momentum
momentum before = momentum after
what has greater momentum a heavy truck at rest or a moving skate board?
moving skate board
In boxing, why is it advantageous to roll with the punch?
rolling with the punchincreases contact time, which decreases the force. Which undergoes the greatest change in momentum
When a cannonball is fired, the momentum of the system (cannon + cannonball) would moment be conserived if its not a vector qauntity?
when no external net force acts on an object or a system of objects, no change of ... The moving automobile has a greater momentum because it is moving. ... A cannonball will have more momentum coming from a long cannon due to the force
Suppose a ball of putty moving horizontally with 1 kg·m/s of momentum collides with and sticks to an identical ball of putty moving vertically with 1 kg·m/s of momentum. What is the magnitude of their combined momentum?
1.41 kg·m/s the eqyation is p={p₁²+p₂²} =2 =1.41 kg•m/s
why would it be a poor idea to have your hand up against the outfield wall when you catch a long fly ball?
Because you need to have that momentum to descease over a little bit of time because if it doesn't have room to move backward, that force isn't going to reduce and it will hurt very badly.
how to find momentum
Momentum = mass x velocity
Can you produce a net impulse on an automobile if you sit inside and push on the dashboard?
Only external forces produce changes in momentum, so no you cannot as it is an internal force
Can the internal forces within a soccer ball produce an impulse on the soccer ball that will change its momentum?
Only external forces produce changes in momentum, so no you cannot as it is an internal force.
Railroad car A rolls at a certain speed and makes a perfectly elastic collision with car B of the same mass. After the collision, car A is observed to be at rest. How does the speed of car B compare with the initial speed of car A?
Since the masses of the cars are the same and car A stops after the collision, the speed of car B has to be similar to the speed with which car A was travelling before it collided with B
Is the impulse-momentum relationship related to Newton's second law?
The impulse-momentum theorem states that the change in momentum of an object equals the impulse applied to it. The impulse-momentum theorem is logically equivalent to Newton's second law of motion
Is it correct to say that, if no net impulse is exerted on a system, then no change in the momentum of the system will occur?
Yes, always. ... Momentum is conserved in elastic and inelastic collisions.
wich undergoes the greatest change in momentum :(1) a base ball that is caught. (2) a base ball caught (3) a base ball caught and thrown back?
a base ball caught and thrown back
