Midterm 1 Review Flashcards
What do atoms consist of?
Every atom is composed of positively
charged nucleus, around which are
distributed a number of negatively
charged electron
What was formed by the big bang?
Hydrogen and helium
How were heavier elements than hydrogen and helium formed?
Nuclear fusion of stars
what is average speed?
distance/time
instaneous speed
speed at each moment that is the # your speedometer measures
what is velocity?
speed & direction
what is acceleration?
change in velocity per unit time
If velocity is changing rapidly,
Big acceleration
If velocity is changing slowly,
Small acceleration
If velocity is constant,
No acceleration
If velocity is decreasing,
Negative acceleration
Due to air resistance, a feather will
a feather will… fall slowly
If we remove air, a feather & a coin or a brick
a feather & a coin or a brick will fall w/ the same acceleration
All objects fall with a _ acceleration
constant
What happens in velocity in free fall?
v=gt or v=10t. With each second of the fall, speed increases by 10 m/s
At 5m, how many seconds of fall?
1 second of fall
At 20m, how many seconds of fall?
2 seconds of fall
At 45m, how many seconds of fall?
3 seconds of fall
If I drop a bullet at the same time I shoot a bullet horizontally, which will hit the ground first? (at same height)
Hit at the same time bc they fall at the same rate. Horizontal motion has no effect on vertical motion
