Physics Exam I

Question 1

What is rest energy? What is it proportional to?

Answer 1

it is the amount of energy an object possesses simply as a consequence of having mass; directly proportional to mass; E = mc^2

Question 2

What is the difference between mass and weight?

Answer 2

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)

Question 3

How many km in 1 mi?

Answer 3

1 mi = 1.609km

Question 4

How many meters in 1 foot?

Answer 4

1 ft = 0.3048m

Question 5

How many kg in 1 pound? how many grams?

Answer 5

1 lb = 0.454 kg = 453.6 g

Question 6

How many L in one ounce?

Answer 6

1 oz = 0.0296 L

Question 7

How many sigfigs: 123

Answer 7

3

Question 8

How many sigfigs: 1.230 x 10^2

Answer 8

4

Question 9

How many sigfigs? 123.000

Answer 9

6

Question 10

How many sig figs? 1.23 x 10^2

Answer 10

3

Question 11

How many sig figs? 0.12300 x 10^3

Answer 11

5

Question 12

rule for multiplying and dividing sig figs?

Answer 12

number with least amount of sig figs is the amount of sig figs in final answer

Question 13

adding or subtracting sig figs

Answer 13

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

Question 14

volume of a sphere

Answer 14

4/3pir^3

Question 15

displacement and distance

Answer 15

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

Question 16

average velocity

Answer 16

change in position over change in time

Question 17

velocity and acceleration in same direction

Answer 17

speeding up

Question 18

velocity and acceleration going in opposite directions

Answer 18

slowing down

Question 19

What happens to acceleration if instantaneous velocity is 0?

Answer 19

There can still be acceleration! maybe instantaneous velocity is zero bc the object is changing directions

Question 20

Which mean that there is an acceleration?
a. speeding up
b. constant velocity
c. changing direction
d. slowing down

Answer 20

a, c, and d

Question 21

what does instantaneous acceleration (aka acceleration) show

Answer 21

how the velocity is changing at a given instant

Question 22

What does the direction of the slope of a vx-t graph tell us about acceleration?

Answer 22

positive - postive a
negative - negative a

Question 23

constant acceleration is when

Answer 23

velocity of an object changes at a steady rate