Physics Exam I Flashcards
What is rest energy? What is it proportional to?
it is the amount of energy an object possesses simply as a consequence of having mass; directly proportional to mass; E = mc^2
What is the difference between mass and weight?
mass is constant no matter where you are, but weight is dependent on gravity (you way different on the moon but your mass is the same)
How many km in 1 mi?
1 mi = 1.609km
How many meters in 1 foot?
1 ft = 0.3048m
How many kg in 1 pound? how many grams?
1 lb = 0.454 kg = 453.6 g
How many L in one ounce?
1 oz = 0.0296 L
How many sigfigs: 123
3
How many sigfigs: 1.230 x 10^2
4
How many sigfigs? 123.000
6
How many sig figs? 1.23 x 10^2
3
How many sig figs? 0.12300 x 10^3
5
rule for multiplying and dividing sig figs?
number with least amount of sig figs is the amount of sig figs in final answer
adding or subtracting sig figs
result should have the same number of digits to the right of the decimal point as the input with the fewest digits to the right of the decimal point
volume of a sphere
4/3pir^3
displacement and distance
distance can’t be negative bc you add up all lengths even if going backwards
if you swim there and back in a pool your displacement is zero
average velocity
change in position over change in time
velocity and acceleration in same direction
speeding up
velocity and acceleration going in opposite directions
slowing down
What happens to acceleration if instantaneous velocity is 0?
There can still be acceleration! maybe instantaneous velocity is zero bc the object is changing directions
Which mean that there is an acceleration?
a. speeding up
b. constant velocity
c. changing direction
d. slowing down
a, c, and d
what does instantaneous acceleration (aka acceleration) show
how the velocity is changing at a given instant
What does the direction of the slope of a vx-t graph tell us about acceleration?
positive - postive a
negative - negative a
constant acceleration is when
velocity of an object changes at a steady rate
