Download 1st semester physci Final Exam review

1st semester physci Final Exam review
kinetic energy = ½•mass(kg)•velocity2(m/sec)
%efficiency= ideal Forceyou/actual Forceyou •100
Force (Newtons) = Mass (kg) • acceleration (m/sec2)
On earth 1 kg = 9.8 Newtons
4 quarts=1 gallon
IMA= Distanceyou/Distanceload = Forceload/Forceyou
Work (Joules) = Force (Newtons) • Distance (meters)
Ideally, Work = Forceyou•Distanceyou=Forceload•Distanceload
.946 liters = 1 quart
1609.3 meters = 1 mile
1)
2)
3)
4)
5)
A kilogram is equal to ________________ grams (memorize what the prefix “kilo-“ means)
A kilometer is equal to ________________ meters
Convert 25 centimeters to meters __________________
(memorize what the prefix “centi-“ means)
Convert 256 kiloliters to milliliters __________________
(memorize what the prefix “milli-“ means)
In a scientific experiment, the one thing that is changed from the experimental group to the control group is called the
__________________ variable.
6) What property of matter would you want to measure to determine if it would float in water or not? ____________________
7) Write the following numbers in scientific notation with correct sig figs:
a. 90,000
_________________________
b. 457000 __________________________
c. .00000008 __________________________
d. 10000.001 __________________________
8) Perform the following calculations and express your answer with the correct number of sig figs in scientific notation:
a. (3.14 X 108)(2.18 X 106) =
b.
(3.14 X 108) / (2.18 X 106) =
c.
(186)/ (7.89 X 1014) =
9) The speed of light is 2.99 X 108 m/sec. What is this speed in miles per hour?
State the number of significant figures in each of the following numbers:
10) .000175 _____
11) 100.0 _____ 12) 600 ______ 13) 637 _____
15) 7,847,001 _____
16) 485.005 _____
17) 6.0080 ______
20) .08 _____
21) 15,001,010 _____
22) 10 _____
14) 634,000 _____
18) 7.501 X 108 ____
19) 4.0 ______
23) A graduated cylinder has water (which has a density of 1.0 g/ml at 4 0C) in it and reads 30.5 mL. An irregular shaped metal is
placed in the graduated cylinder and is completely submerged; the water level then reads 47.7 mL. The object is dried and placed on a
triple beam balance and its mass is found to be 23.07 grams.
What is the density of this metal?
24) How many miles are there in 43.0 kilometers?
25) How many liters are there in a gallon?
26)You notice a pattern as you walk along the beach. For every 4 grains of brown sand there are 5 grains of black sand. For every 3
gallons of water that rain down you must shake out your rubber boots 7 times. For every 2 times you shake out your boots you spot
5 generic sea shells on the beach. For every two people that pass by you measure 9 gallons of rain which has fallen from the sky. If
you pass by 6 people on your walk down the beach, how many generic sea shells would you expect to see (answer in 3 sig figs)?
27) To calculate the change in gravitational potential energy you multiply the weight of an object times the distance that it is above the
ground [∆GPE = weight (N) • ∆height (m)]. If each floor of a building is 3.69 meters high, on what floor would an 82 kg person be if he
has 44,560 Joules of gravitational potential energy?
28) Draw the support strings for the pulley system to the right so it has an IMA of 5
(assume massless pulleys)
b. Without friction, what Force
would you need to exert to hold the 50.0 N mass in place ?
c. If the machine is 66.0% efficient,
what force would you have to exert?
N
N
50 N
29) You are pushing a 1000 kg car up a 4% grade. This means the car moves 1 m vertically for every 4 m it moves horizontally.
a.
How many Joules of work are done lifting the car 3.00 meters?
3 meters
4%
b.
How many Newtons of force would you exert by holding the car in place assuming there is no friction (hint: to find the
hypotenuse of a right triangle a2 + b2 = c2)?
30) What is the weight of a 40.0 kg ball of twine in Newtons?
31) What is the kinetic energy of a 7.00 kg bowling ball traveling at a rate of 2.30 m/sec?
32) You use a pulley system with a mechanical advantage of 3 to lift a 200.0 Newton object off the ground. What force do you have to
exert?
33) Describe the VELOCITY and ACCELERATION of the person in this distance vs. time graph.
b
c
a
34) What is the definition for a Newton of force, and how does Newton’s second law relate?
4
6 Time (s)
35) Using the equation to calculate work, explain why a Joule of energy is the same thing as a Newton•Meter of energy and why this is
the same unit as a kg•m2/sec2.
Answers: 1) 1000 g
2) 1000 m
3) .25 m
4) 256,000,000 ml or 2.56 X 108 ml 5) manipulated 6) density
4
5
-8
7a) 9 X 10
7b) 4.57 X 10
7c) 8 X 10
7d) 1.0000001 X 104
8a) 6.84 X 1014 8b) 1.44 X 102
-13
8
8c) 2.36 X 10
9) 6.69 X 10 miles/hour 10) 3
11) 4
12) 1
13) 3
14) 3
15) 7
16) 6
17) 5
18) 4
19) 220) 1
21) 7
22)1
23) 1.34 g/ml, no it would not float 24) 26.7 miles
25) 3.78 liters
26) 157 generic sea
shells 27) 15th floor
28a) 5 supporting strings 28b) 10 N
28c) 15.2 N
29a) 29,400 J
29b) 2377 N
30) 392 N
31) 18.5 J
32) 66.67 N
33a) Increasing velocity and constant, positive acceleration
33b) 0 velocity and 0 acceleration 33c) velocity is constant and negative, and acceleration is 0
34) DF Newton= the force it
takes to cause a 1kg object to increase in velocity 1 m/sec for every second it moves. Newton’s 2nd law is force=mass•acceleration
35) Work=Force•Distance, and the measure of force is Newtons and Distance is meters (N•m). A Newton is a kg•m/sec2, and this
multiplied by a meter is a kg•m2/sec2.