p7 Flashcards
momentum
inertia in motion
impulse
change in momentum
conservation of momentum
in the absence of an external force, the momentum of a system remains the same
elastic collision
collision without objects being peramnently deforemed and without generating heat
inelastic collision
collision where objects become tangled or attached or permanently deformed
What is the formula for momentum? -
mass x speed
What is the difference between momentum and inertia? -
inertia is an object’s tendency to stay in motion or at rest until another force acts upon it; momentum is an object’s inertia in motion
What is the momentum of a 80 kg object moving 30 m/s? -
2400 kg m/s
Why does bungee jumping with a bungee cord hurt less than bungee jumping with a chain? (the word ‘time’ should be included in your answer)
The bungee cord increases the time that you are falling, which increases your impulse and decreases your momentum
If a car (1,000kg and 20 m/s) collides with a truck (2,000kg and 0m/s) and gets stuck together, what is their velocity after the crash?
(1,000 x 20 = 20,000 - momentum of car) and (2,000 x 0 = 0 - momentum of truck) so (20,000 + 0 = 20,000 - momentums added together). (1,000 + 2,000 = 3,000 - total mass of truck and car). (20,000 / 3,000 = 6.67 - divide momentum by mass). Their velocity is 6,67 m/s going left?? In the direction that the car is traveling.