Homework Solutions
Physics 120 Fall 2006
Chapter 8 4,12,19,23,25,33,44,45,58,61
rev 2 rad 1 min
4.
The initial angular velocity is o = 6500
= 681rad s . Use the
min 1 rev 60 sec
definition of angular acceleration.
0 681rad s
=
=
= 227 rad s 2 2.3 10 2
Homework Solutions
Physics 120 Fall 2006
Chapter 7 4,10,17,22,27,33,34,47,50
4. The throwing of the package is a momentum-conserving action, if the water resistance is ignored. Let A
represent the boat and child together, and let B represent the package.
Homework Solutions
Physics 120 Fall 2006
Chapter 4 - 5,6,19,23,32,34,40,43,52,79
5.
(a) The 20.0 kg box resting on the table has the free-body diagram shown. Its weight
(
)
2
is mg = ( 20.0 kg ) 9.80 m s = 196 N . Since the box is at rest, the net force o
Physics 120
Professor J. Combs
Anna Phe
Lab Partner: Crystal Tse
30 June, 2010
The Atwoods Machine
Introduction
The purpose of this lab is to measure and predict the acceleration of one of the masses by
reproducing the Attwoods Machine experiment which al
1. (24 points) Answer the following questions.
(a) Balli (m = 1 kg), ball2 (m =2 kg), and ball3 (m =3 kg) were all launched to the
right from point A. They were launched with different speeds and angles. In the
diagram, the balls are shown at various time
Physics 120
Professor J. Combs
Crystal Tse
Lab Partner: Anna Phe
29 June, 2010
The Atwoods Machine
Introduction
In this laboratory, we wanted to measure the acceleration of one of the masses by
reproducing the Attwoods Machine experiment. The experiment d
Dr. Fritz Wilhelm
Lab6 Free Fall Movement with Constant Acceleration
Marilia Del Aguila Montero Physics 111-2625; 03/23/2010
Finding the target area of a spring-gun
Theory:
Motion with constant acceleration.
vo
x
t
Y=h
Constant acceleration g 9.8m / s 2
Homework Solutions Physics 120
Chapter 15 1,2,5,9,11,18,19,24,30,36,42
1.Use the first law of thermodynamics, Eq. 15-1, and the definition of internal energy, Eq. 14-1. Since
the work is done by the gas, it is positive.
(a) Since the temperature does not
Homework Solutions
Physics 120 Fall 2006
Chapter 14 1, 6,15,20,22,26,33,38,57
1.
The kcal is the heat needed to raise 1 kg of water by 1 Co. Use the definition to find the heat needed.
1 kcal 4186 J
7
( 30.0 kg ) 95o C 15o C
= 1.0 10 J
o
( 1kg ) 1C 1 kc
Homework Solutions Physics 120
Chapter 13 27,30,33,42,48,55
27. Use the relationship that T ( K ) = 5 T
9
T ( K ) = 5 T
9
T
30.
( F ) 32 + 273.15
( F ) 32 + 273.15 .
o
o
( F ) = [ T ( K ) 273.15] + 32 = [ 0 273.15] + 32 =
o
9
5
9
5
459.67 o F
Assume the a
Homework Solutions
Physics 120 Fall 2006
Chapter 9 2,7,12,18,27
2.
7.
The torque is the force times the lever arm.
= Fr = ( 58 kg ) ( 9.8 m s 2 ) ( 3.0 m ) = 1.7 10 3 m g , clockwise
N
The CG of each beam is at its center. Calculate torques about the
lef
Homework Solutions
Physics 120 Fall 2006
Chapter 5 - 5,7,19,35,40,50,53,56,77
5.
The orbit radius will be the sum of the Earths radius plus the 400 km orbit height. The orbital period is
about 90 minutes. Find the centripetal acceleration from these data.
Homework Solutions
Physics 120 Fall 2006
Chapter 3 - 2,6,13,21,31,39,40,57,64,71
2.
The truck has a displacement of 18 + ( 16 ) = 2 blocks north and 10 blocks
east. The resultant has a magnitude of
2 + 10 = 10 blocks and a direction
2
2
tan 1 2 10 = 11o n
Homework Solutions
Physics 120 Fall 2006
Chapter 2 - 8,12,19,28,37,52,69
8.
The speed of sound is intimated in the problem as 1 mile per 5 seconds. The speed is calculated by:
distance 1mi 1610 m
speed =
=
= 300 m s .
time
5 s 1 mi
Note that only 1 si
1. (24 points) Answer the following questions.
(a) Ball 1 (m = 1 kg), ball 2 (m =2 kg), and ball3 (m =3 kg) were all launched to the
right from point A. They were launched with different speeds and angles. In the
diagram, the balls are shown at various ti