General Physics Exam 2 Study Guide PDF

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Exam 2 Formula Sheet Work and Energy: Static and Rotational Dynamics:

W Fd cos T PE mgh 1 KE mv 2 2

W gravity

if Wnc

0  KE i  PE i

PE

KE f  PE f

W t Linear Momentum:

& mv

& Impulse  I F't & & & & ' p p f  pi Faverage 't 't m1 x1  m2 x2    m n x n x centerof m1  m2    mn mass Rotational Motion:

Z T

T

I

¦mr

v2 r 1 f

L

W ext

2

i i

m1 r1  m 2 r2    mn rn 2

1 2 IZ 2

IZ 0  I 1Z 1

I 2Z 2

AZ

v max a

A Z 2 cosZt

AZ 2 2S Z 2Sf T Simple Harmonic Oscillator amax

k m

m k Simple Pendulum

Z 2r

Z

2S T Zt  const.angular velocity 2Sf

°

Z 02  2DT¾ const.angular acceleration

° 1 Z  Z 0 t°° 2 ¿

2

Simple Harmonic Motion: F kx  Hooke' s Law 1 2 PE elastic kx 2 x A cosZt v  AZ sin Z t

T

T Z 0t  12 Dt 2 ½ ° Z Z 0 D t ° Z2

ID

Z

s rT v rZ aT rD

T

6W

KER

P

aC

rF sin T

i

1 §1 2 2· ¨ mv f  mv i ¸  mgh f  mghi    2 ©2  ¹ ' 'KE

& p

lF

' KE

Wnet

W nc

1 2 1 2 mv f  mvi 2 2   mg h f  hi

6W

T

2S

g L 2S

L g

2

Fluids: Patm 1.013 u 10 5 Pa m U V F P A P Patm  Ugh

FB

W fluid

U FluidV Fluid

g

Displaced

volume flow rate  A1v1 P1 

1 2 Uv 1  Ugy1 2

P2 

A2 v 2 1 2 Uv 2  Ugy2 2

Additional Formulas and Constants: g 9.8 m / s 2 & & ¦ F ma

fk

P k FN

Area of a circle  A

πr 2

Volume of a sphere  v

U w 1000 kg / m3

4 3

Sr 3

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

General Physics 203 1 Practice Final Exam 1. City (A) lies 30.0 km directly south of city (B). A bus, beginning at city (A) travels 50.0 km at 37.0° north of east to reach city (C). How far and in what direction must the bus go from city (C) to reach city (B)? a. 20.0 km, west b. 40.0 km, west c. 80.0 km, west d. 40.0 km, east e. 80.0 km, east 2. A car traveling along a road begins accelerating with a constant acceleration of 1.5 m/s2 in the direction of motion. After traveling 392 m at this acceleration, its speed is 35 m/s. Determine the speed of the car when it began accelerating. a. 1.50 m/s b. 7.00 m/s c. 34.0 m/s d. 49.0 m/s e. 2.30 m/s 3. A ball is thrown vertically upward from the surface of the earth. The ball rises to some maximum height and falls back toward the surface of the earth. Which one of the following statements concerning this situation is true if air resistance is neglected? a. As the ball rises, its acceleration vector points upward. b. The ball is a freely falling body for the duration of its flight. c. The acceleration of the ball is zero when the ball is at its highest point. d. The speed of the ball is negative while the ball falls back toward the earth. e. The velocity and acceleration of the ball always point in the same direction. 4. An eagle is flying due east at 8.90 m/s carrying a gopher in its talons. The gopher manages to break free at a height of 12.0 m. What is the magnitude of the gopher's velocity as it reaches the ground? Note: effects of air resistance are not included in this calculation. a. 22.0 m/s b. 18.0 m/s c. 11.0 m/s d. 9.80 m/s e. 8.90 m/s 5. A cannon ball at ground level is aimed 30.0° above the horizontal and is fired with an initial speed of 125 m/s. How far away from the cannon will the cannonball hit the ground? a. 125 m b. 138 m c. 695 m d. 1040 m e. 1380 m

General Physics 203 2 Practice Final Exam 6. The pulley system shown in the figure is in static equilibrium. Given that the mass (m1) is 8.40 kg and the coefficient of static friction between mass (m1) and the surface on which it rests is 0.30, what is the maximum mass that (m2) can have for which the system will still remain in equilibrium? a. 0.036 kg b. 5.04 kg c. 28.0 kg d. 2.52 kg e. 5.88 kg

7. A rope connects boat (A) to boat (B). Boat A starts from rest and accelerates to a speed of 9.50 m/s in a time t = 47.0 s. The mass of boat B is 540 kg. Assuming a constant frictional force of 230 N acts on boat B, what is the magnitude of the tension in the rope that connects the boats during the time that boat A is accelerating? a. 340 N b. 1270 N c. 230 N d. 860 N e. 160 N 8. A boy is whirling a stone around his head by means of a string. The string makes one complete revolution every second; and the magnitude of the tension in the string is F. The boy then speeds up the stone, keeping the radius of the circle unchanged, so that the string makes two complete revolutions every second. What happens to the tension in the sting? a. The magnitude of the tension is unchanged. b. The magnitude of the tension reduces to half of its original value, F/2. c. The magnitude of the tension increases to twice its original value, 2F. d. The magnitude of the tension increases to four times its original value, 4F. e. The magnitude of the tension reduces to one-fourth of its original value, F/4. 9. An indoor track is to be designed such that each end is a banked semi-circle with a radius of 24.0 m. What should the banking angle be for a person running at speed v = 6.00 m/s? a. 8.70° b. 11.0° c. 14.0° d. 22.0° e. 45.0° 10. An automobile approaches a barrier at a speed of 20.0 m/s along a level road. The driver locks the brakes at a distance of 50.0 m from the barrier. What minimum coefficient of kinetic friction is required to stop the automobile before it hits the barrier? a. 0.40 b. 0.50 c. 0.60 d. 0.70 e. 0.80

General Physics 203 3 Practice Final Exam 11. How much power is needed to lift a 75.0-kg student vertically upward at a constant speed of 0.33 m/s? a. 12.5 W b. 25.0 W c. 115 W d. 230 W e. 243 W 12. An elevator supported by a single cable descends a shaft at a constant speed. The only forces acting on the elevator are the tension in the cable and the gravitational force. Which one of the following statements is true? a. The magnitude of the work done by the tension force is larger than that done by the gravitational force. b. The magnitude of the work done by the gravitational force is larger than that done by the tension force. c. The work done by the tension force is zero joules. d. The work done by the gravitational force is zero joules. e. The net work done by the two forces is zero joules. 13. A block of mass (m) is released from rest at a height (R) above a horizontal surface. The acceleration due to gravity is (g). The block slides along the inside of a frictionless circular hoop of radius (R). What is the magnitude of the normal force exerted on the block by the hoop when the block reaches the bottom of the hoop? a. zero !" #

b. $ c. mg d. 2mg e. 3mg

!

14. A stationary 4.00-kg shell explodes into three pieces. Two of the fragments have a mass of 1.00 kg each and move along the paths shown with a speed of 10.0 m/s. The third fragment moves upward as shown. What is the speed of the third fragment? a. b. c. d. e.

zero 1.00 m/s 5.00 m/s 10.0 m/s 20.0 m/s

15. A circular disk of radius 2.0 m rotates, starting from rest, with a constant angular acceleration of 20.0 rad/s2. What is the tangential acceleration of a point on the edge of the disk at the instant that its angular speed is 1.0 rev/s? a. 40 m/s2 b. 79 m/s2 c. 110 m/s2 d. 120 m/s2 e. zero

General Physics 203 4 Practice Final Exam 16. A string is tied to a doorknob 0.720 m from the hinge as illustrated in the figure. At the instant shown, the force applied to the string is 5.00 N. What is the magnitude of the torque on the door? a. b. c. d. e.

2.10 N⋅m 3.00 N⋅m 1.00 N⋅m 0.780 N⋅m 0.600 N⋅m

17. Consider the following four objects: a hoop, a flat disk, a solid sphere, and a hollow sphere. Each of the objects has mass (M) and radius (R). The axis of rotation passes through the center of each object, and is perpendicular to the plane of the hoop and the plane of the flat disk. Which of these objects requires the largest torque to give it the same angular acceleration? a. the solid sphere b. the hollow sphere c. the hoop d. the flat disk e. both the solid and the hollow spheres 18. A 1.00-kg block oscillates with a frequency of 10.0 Hz at the end of a certain spring. The spring is then cut into two halves. The 1.00-kg block is then made to oscillate at the end of one of the halves. What is the frequency of oscillation of the block? a. 5.00 Hz b. 10.0 Hz c. 14.0 Hz d. 20.0 Hz e. 40.0 Hz 19. A 2.00-kg object is attached to a spring (k = 55.6 N/m) that hangs vertically from the ceiling. The object is displaced 0.045 m vertically. When the object is released, the system undergoes simple harmonic motion. What is the magnitude of the maximum acceleration of the object? a. 1.30 m/s2 b. 2.30 m/s2 c. 4.40 m/s2 d. 9.80 m/s2 e. 11.0 m/s2 20. A column of oil of height 70.0 cm supports a column of an unknown liquid as suggested in the figure (not drawn to scale). Assume that both liquids are at rest and that the density of the oil is 840 kg/m3. Determine the density of the unknown liquid. a. b. c. d. e.

3.20 × 102 kg/m3 2.20 × 103 kg/m3 2.60 × 103 kg/m3 3.60 × 103 kg/m3 4.90 × 103 kg/m3

General Physics 203 5 Practice Final Exam 21. Water enters a pipe of diameter 3.00 cm with a velocity of 3.00 m/s. The water encounters a constriction where its velocity is 15.0 m/s. What is the diameter of the constricted portion of the pipe?! a. 0.440 cm b. 0.750 cm c. 1.30 cm d. 1.60 cm e. 6.70 cm 22. A thin, circular disc is made of lead and has a radius of 0.0350 cm at 20.0 °C. Determine the change in the area of the circle if the temperature is increased to 625.0 °C. The coefficient of linear thermal expansion for lead is 29.0 × 10–6/C°. a. 4.33 × 10–5 cm2 b. 1.36 × 10–4 cm2 c. 1.89 × 10–4 cm2 d. 3.19 × 10–4 cm2 e. 5.92 × 10–4 cm2 23. After working a 550-g iron horseshoe with a temperature of 460 °C on an anvil, a Ferrier drops it into a bucket that contains 11.0 kg of water with an initial temperature of 24.0 °C. Assuming no heat is transferred to the environment, determine the final temperature of the horseshoe in the bucket of water when thermal equilibrium is achieved. The specific heat capacity of iron is 452 J/kg · C°. The specific heat of water is 4186 J/kg · C°. a. 26.0 °C b. 34.0 °C c. 41.0 °C d. 49.0 °C e. 52.0 °C 24. A 0.030-kg ice cube at 0 °C is placed in an insulated box that contains a fixed quantity of steam at 100 °C. When thermal equilibrium of this closed system is established, its temperature is found to be 23 °C. Determine the original mass of the steam at 100 °C. a. b. c. d. e.

0.170 g 1.70 g 2.50 g 4.80 g 5.00 g

25. Two moles of a monatomic gas with an rms speed of 294 m/s are contained in a tank that has a volume of 0.12 m3. If each gas particle has a mass of 8.220 × 10–26 kg, what is the absolute pressure of the gas? a. 2.1 × 105 Pa b. 1.1 × 104 Pa c. 4.8 × 104 Pa d. 2.4 × 104 Pa e. 3.0 × 104 Pa

General Physics 203 6 Practice Final Exam 26. A sample of neon gas at 20 °C is confined to a cylinder with a movable piston. The gas is then heated until its pressure is doubled. What is the final temperature of the gas? a. 10 °C b. 40 °C c. 313 °C d. 586 °C e. This cannot be found since the final and initial volumes are unknown. 27. Under which of the following conditions would you expect real gases to approach ideal behavior? a. low temperature and low pressure b. high temperature and low pressure c. low temperature and high pressure d. high temperature and high pressure e. high temperature and high density 28. During one stage of a reversible process, the temperature of an ideal gas remains constant as its volume is decreased. Which one of the following statements concerning this situation is true? a. The process is adiabatic. b. The pressure of the gas decreases in this process. c. Heat flows out of the gas and into the surroundings. d. The gas does "positive" work on its surroundings. e. The average kinetic energy of the gas molecules increases. 29. Heat is added to a sample of an ideal monatomic gas. Which one of the following statements is necessarily true? a. The gas must expand. b. The gas must do work. c. The type of change that will occur depends on the conditions of the gas when the heat was added. d. The gas must change phase. e. The temperature of the gas must increase. 30. An ideal gas absorbs 750 J of heat as it performs 625 J of work. What is the resulting change in temperature if there are 1.3 moles of the gas in the system? a. –8.6 K b. –4.3 K c. 7.7 K d. 9.6 K e. 23 K 31. The tension in a taut rope is increased by a factor of 9. How does the speed of wave pulses on the rope change, if at all? a. The speed remains the same. b. The speed is reduced by a factor of 3. c. The speed is reduced by a factor of 9. d. The speed is increased by a factor of 3. e. The speed is increased by a factor of 9.

General Physics 203 7 Practice Final Exam 32. According to US government regulations, the maximum sound intensity level in the workplace is 90.0 dB. Within one factory, 32 identical machines produce a sound intensity level of 92.0 dB. How many machines must be removed to bring the factory into compliance with the regulation? a. 2 b. 8 c. 12 d. 16 e. 24 33. Two golf carts have horns that emit sound with a frequency of 394 Hz. The golf carts are traveling toward one another, each traveling with a speed of 9.50 m/s with respect to the ground. If one of the drivers sounds her horn, what frequency does the other driver hear? The speed of sound at the golf course is 345 m/s. a. 378 Hz b. 394 Hz c. 408 Hz d. 416 Hz e. 424 Hz 34. A guitar string has a linear density of 8.30 × 10–4 kg/m and a length of 0.660 m. The tension in the string is 56.7 N. When the fundamental frequency of the string is sounded with a 196-Hz tuning fork, what beat frequency is heard? a. 6.00 Hz b. 4.00 Hz c. 12.0 Hz d. 8.00 Hz e. 2.00 Hz 35. Vibrations with frequency 6.00 × 102 Hz are established on a 1.33-m length of string that is clamped at both ends. The speed of waves on the string is 4.00 × 102 m/s. How many antinodes are observed for the resulting standing wave pattern? a. 2 b. 3 c. 4 d. 5 e. 6...