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1 PHYSICS 30 - FINAL EXAM REVIEW Use these questions as a guide for possible final exam type questions. Also, follow this link: You will be directed to the Saskatchewan Online Math and Science Prototype Exams Click on physics 30 and then scroll to the bottom and click on [Enroll With a temporary account]. You will need to enter some basic information including your name and . You will be given a username and password. Scroll to the bottom and click on the link provided. This is your temporary access page. On the right, click on Physics 30. You may now access the Departmental Prototype exams.

2 Part I Multiple choice A ball is thrown straight up. It rises to a height of 11 meters and then falls back and is caught. 1. The ball was airborne for: a) 1.5 s b) 3.0 s c) 4.5 s d) 6.0 s 2. What was the displacement of the ball? a) 0 m b) 11 m c) 22 m d) none of these 3. What was the average speed of the ball? a) 15 m/s b) 0 m/s c) 9.8 m/s d) 7.3 m/s 4. What was the maximum speed of the ball? a) 15 m/s b) 9.8 m/s c) 7.3 m/s d) 5.5 m/s 5. A rock is thrown straight up at a velocity of 22.8 m/s. It will rise to a maximum height of: a) 2.30 m b)1.2 m c) 223 m d) 26.5 m A kid standing on the roof of a 10 m high building throws a snowball straight up as shown. The snowball goes up and then falls into the street below. A vector reference frame is established so that the up direction is positive and down is negative. Questions 6 to 9 refer to the displacement, velocity and acceleration of the snowball. Choose the best answer. 6. Where is the velocity zero? a) at A b) at C c) at A and E d) at E e) at F 7. Where is the velocity negative? a) at A b) at C c) at A and E d) between A and C e) between C and F 8. Where is the displacement zero? a) at A b) at C c) at A and E d) between A and C e) between C and F

3 9. Where is the displacement most negative? a) between C and F b) at C c) at F d) at A and E e) between E and F 10. A car initially travelling at a constant velocity suddenly brakes and comes to rest. Taking the direction of travel as the positive direction, which of the following is true: a) displacement, d is negative b) final velocity, v f is negative c) acceleration, a is negative d) all the above are false 11. Taking up as positive; at the highest point, the acceleration of a projectile is a) 9.8 m/s 2 b) 0 m/s 2 c) -9.8 m/s 2 d) none of the above 12. Which of the following might represent a displacement vector? a) 22 m/s, west b) 24 m c) 45 s d) 30 m, down 13. A 3.5 kg mass is pulled to the right over a level surface by a 5.0 N horizontal force. The mass is found to accelerate at 1.0 m/s 2 to the right. The magnitude of the frictional force is: a) 0 b) 8.5 N c) 1.5 N d) 17.5 N 14. A cable exerts an upward pull of 7.5kN on an elevator weighing 6.0kN at rest. The net force acting on the elevator is: a) 1500 N b) 6000 N c) 7500 N d) N 15. The acceleration of the elevator in the previous question is: a) 1.22 m/s 2 b) 2.45 m/s 2 c) 3.68 m/s 2 d) 4.90 m/s A 1200 kg rocket rises vertically with an upward acceleration of 40.0 m/s 2. Calculate the engine thrust required. a) 9960 N b) 8000 N c) N d) N

4 17. One newton is equivalent to: a) 1 kg m/s b) 1 kg m 2 /s c) 1 J/m 2 d) 1 kg m/s A frog uses a rocket to cross his frozen pond. The rocket produces a thrust of 18 N and no other forces are significant. The rocket has a mass of 100 grams. The acceleration of the frog and rocket is 24 m/s 2. What is the mass of the frog? a) 75 g b) 0.75 kg c) 250 g d) 650 g 19. A model rocket has a mass of 100 g. Its weight on Earth is about a) 100 N b) 10 N c) 1 N d) 0.1 N 20. If the rocket in question 19 has a motor that produces a continuous thrust of 9.0 N, the acceleration of the rocket will be a) 20 m/s 2 b) 40 m/s 2 c) 60 m/s 2 d) 80 m/s The rocket in question 19 is launched straight up (initially at rest). Assuming negligible air resistance, its altitude after 1.2 seconds is a) 115 m b) 58 m c) 38 m d) 146 m 22. A rocket accelerates upward. Air resistance is negligible. Which of the following free-body diagrams fits this situation best? 23. A crate is dragged across a level floor by a rope which is parallel to the floor. The crate moves at constant speed. Which of the following free-body diagrams fits this situation best?

5 24. A heavy truck and a light truck collide. According to one of Newton s Laws, the force acting on the light truck is the force on the heavy truck. a) greater than b) less than c) equal to d) irrelevant 25. The tendency of an object to resist any change to its motion is known as. a) force b) mass c) inertia d) momentum 26. According to the internet encyclopedia Wikipedia, the perpendicular component of the contact force exerted by, for example, the surface of a floor or wall, on an object, preventing the object from entering the floor or wall is called the force. a) gravitational b) normal c) tension d) frictional 27. If an object moves with constant velocity, it means that a) there is a force pushing the object along b) no forces are acting on the object c) there is no net force d) only the force of gravity acts 28. A car initially moving to the right, slows down as the brakes are applied. Which row in the table gives the correct directions for the velocity v, acceleration a and the net force ΣF. a) A b) B c) C d) D Use the following scenario to answer the next three questions A 1.00 kg block at rest on a horizontal frictionless surface is connected to an un-stretched spring (k= 200 N/m) whose other end is fixed (see figure). 29. A 2.00 Kg block moving at 4.00 m/s collides with the 1.00 kg block. If the two blocks stick together after the one dimensional collision, what is their velocity just after that collision (before starting to compress the spring)? a m/s b m/s c m/s d m/s

6 30. The total kinetic energy just after the collision (before starting to compress the spring) is a J b J c J d J 31. What maximum compression in the spring occurs when the blocks momentarily stop? a m b m c m d m 32. A block of mass 10.0 kg starts a distance h = 30.0 m above the bottom of a loop of radius R=5.00 m. Assume friction is negligible. The kinetic energy of the block when it passes by the point P (the top of the loop) is equal to (in Joules): a kj b kj c kj d. 980 J 33. The speed of the block at point P is a m/s b m/s c m/s d m/s Use this scenario for the next two questions: A full draw is the maximum distance that an archer can pull back an arrow. Using the recurve bow shown below, a particular archer requires an average force of 130 N to pull a full draw of 70.0 cm. 34. The spring constant for the recurve bow is a N/m b N/m c. 186 N/m d. 433 N/m 35. The maximum speed of a 20.6 g arrow leaving this bow from a full draw is a m/s b m/s c x 10 3 m/s d x 10 3 m/s 36. In an automobile collision, the severity of injury to the driver can be reduced by an airbag. In a car initially travelling at 100 km/h, the airbag stops a 62 kg driver in 90 ms. The magnitude of average force exerted by the airbag on the driver is a. 6.9 x 10 4 N b. 1.9 x 10 4 N c. 9.6 x 10 3 N d. 6.1 x 10 2 N

7 37. A 2100 kg van collides with a 1200 kg car that is at rest. They lock together and move together at a speed of 4.50 m/s. The initial speed of the van is... a. 4.5 m/s b. 9.0 m/s c. 7.1 m/s d. 2.9 m/s 38. A batter hits a fly ball. The kg baseball moves at a rate of 20.0 m/s at the point where it is 5.00 m above the ground. How much mechanical energy does the baseball have with respect to the ground (assume no air drag)? a J b J c J d J 39. What is the magnitude of the momentum of the baseball from the previous question the instant before it reaches the ground? a kg m/s b kg m/s c kg m/s d kg m/s The Channel Tunnel (or Chunnel ) is an underwater train tunnel built to carry high-speed trains under the English Channel between Britain and France. The 2.40 x 10 6 kg train travels at a constant speed of 145 km/h (40.3 m/s) from the entrance to the exit of the Chunnel. 40. The kinetic energy of the train travelling in the Chunnel at point A is a x 10 7 J b x 10 9 J c x 10 9 J d x J 41. Which of the following statements best describes the inelastic collision shown above? a. Momentum is not conserved, and kinetic energy is not conserved. b. Momentum is conserved, but kinetic energy is not conserved. c. Momentum is not conserved, but kinetic energy is conserved. d. Momentum is conserved, and kinetic energy is conserved.

8 42. A force of 20 N east acts on a 5.0 kg object over a distance of 12 m. If the object starts with an initial velocity of 20 m/s [E], its final kinetic energy, if friction is neglected is, a. 240 J b. 290 J c. 1.2 kj d. 2.2 kj 43. The work done in the previous question is a. 240 J b. 290 J c. 1.2 kj d. 2.2 kj 44. A force of 30 N is applied to a 6.0 kg mass over a distance of 10 m. If the final speed of the mass is 6.0 m/s, the energy lost due to friction is a. 300 J b. 280 J c. 190 J d. 110 J Use the following scenario for the next 4 questions. A boy stands on the edge of a cliff 70.0 m high and throws a rock of mass 0.25 kg horizontally at a velocity of 30.0 m/s. 45. The time it takes the rock to contact the water is a s b s c s d s 46. The mechanical energy of the rock at the moment it leaves the boys hand is a J b J c. 284 J d J 47. The rock has a range of a. 183 m b m c. 150 m d. 113 m 48. The final speed of the rock is a m/s b m/s c. 284 m/s d m/s 49. A newly discovered planet, Cosmo has a mass that is 4 times the mass of the Earth. The radius of the Earth is R e. The gravitational field strength at the surface of Cosmo is equal to that at the surface of the Earth if the radius of Cosmo is equal to a. 1 2 R e b. 2R e c. R e d. R e 2

9 50. Satellite X moves around Earth in a circular orbit of radius R. Satellite Y is also in a circular orbit around Earth, and it completes one orbit for every eight orbits completed by satellite X. What is the orbital radius of satellite Y? a. 1 4 R b. 4R c. 1 2 R d. 8R 51. What is the gravitational force between the planet Jupiter and the sun? a N b N c N d N 52. Find the orbital velocity of a satellite if it orbited m above the surface of the earth. a m/s b m/s c m/s d m/s 53. Find the orbital period (in years) of the planet Pluto around the sun. a y b. 248 y c y d y 54. A spaceship moves at a speed of 0.95 c away from the Earth. It shoots a star wars torpedo toward the Earth at a speed of 0.90 c relative to the ship. What is the velocity of the torpedo relative to the Earth? (The direction in which the spaceship moves is the positive direction.) a c b c c c d c e A fancy sports car passes Big Ben (large clock in England) at a speed of 0.60 c. What time interval will the driver measure for a one-second interval on the large clock? a s b. 0.8 s c s d. 0.6 s e. 1.0 s 56. A fancy sports car passes Big Ben (large clock in England) at a speed of 0.60 c. What time interval will a pedestrian measure for a one-second interval on the large clock? a s b. 0.8 s c s d. 0.6 s e. 1.0 s

10 57. A 30-year-old woman takes a trip on a rocket, leaving her 20-year-old brother behind. She travels at a speed of 0.8 c, and is gone 20 years, according to the younger brother. When she returns, how many years older/younger is she than her brother? a. 12 years younger b. 2 years older c. 3 years younger d. 8 years older 58. A starship navigator measures the distance between the Earth and the sun. If the ship is moving at a speed of 0.90 c, instead of obtaining 150 million kilometers, the navigator measures a distance (in millions of km) of a. 65. b. 48. c d An electron has a speed of 0.90 c. What is the difference between its relativistic momentum and its nonrelativistic momentum (in kg m/s)? a b c d A proton s rest mass is kg. Calculate its total energy when it is accelerated to a speed of 0.80 c. a J b J c J d J 61. A proton s rest mass is kg. Calculate its kinetic energy when it is accelerated to a speed of 0.80 c. a J b J c J d J 62. A proton has a total energy of J. How fast is it moving? a. 0.9 c b. 0.8 c c. 0.7 c d. 0.6 c Use this scenario for the next two questions Electrostatic Spray Nozzles Crop-dusting planes release pesticide through electrostatic spray nozzles in order to minimize pesticide waste. The centre of each nozzle contains a needle with a positive charge. The presence of the charged needle causes the droplets passing through the opening to become charged. When the charged droplets fall onto the leaves of the crop, they are less likely to be carried away by the wind.

11 63. The droplets leave the nozzle with a a. negative charge caused by the movement of protons onto the needle b. positive charge caused by the movement of electrons onto the needle c. positive charge caused by the movement of protons onto the droplets d. negative charge caused by the movement of electrons onto the droplets 64. The charged droplets are kept from being blown off of the leaves by the wind because the charged droplets a. gain electrons from the air and transfer them to the leaves b. fall faster through the air because they have similar charges c. induce an opposite charge on the leaves so they are attracted to them d. repel each other and spread out, thus the effect of the wind is minimized Electrostatics Two particles, I and II, of equal mass have opposite charges. The negative charge on particle I is three times greater than is the positive charge on particle II. The particles are placed 9.0 cm apart. 65. If the charge of particle II is equivalent to two elemental charges (2e), then the electric force between the particles is a x N b x 10-6 N c x N d x N 66. If the charges in the previous question are moved toward each other until they are 6.0 cm apart. The force between them becomes a x N b x 10-6 N c x N d x N Use the following information to answer questions the next 3 questions. A student is using a laptop computer for 30.0 minutes. The laptop computer runs on a battery that produces an electric potential of 20.0 V. Due to the nature of its electrical components, the laptop computer draws a total current of 3.25 A. 67. The number of electrons that leave the negative terminal of the battery would be: a x electrons. b x electrons. c x electrons. d x electrons. 68. The total electrical power developed by the laptop computer is a W b W c W d W 69. The amount of electrical energy consumed would be a x 10 5 J b x 10 5 J c x 10 4 J d x 10 2 J

12 70. The left diagram shows a positively charged particle is moving with velocity v in a magnetic field B. Using the right diagram, the direction of the magnetic force on the particle is a. 1 b. 2 c. 3 d. 4 e An electron is traveling east with an instantaneous velocity of m/s when it enters a uniform magnetic field of 0.45 T that points 35 north of east. What are the magnitude and direction of the force on the electron? a N up b N down c N up d N down e N up 72. If the magnetic field vector is directed toward the north and a positively charged particle is moving toward the east, what is the direction of the magnetic force on the particle? a. up b. west c. south d. down e. east 73. A long straight wire parallel to the y axis carries a current of 6.3 A in the positive y direction. There is a uniform magnetic field = 1.5 T in the positive x direction. The force per unit length on the wire is approximately a. 6.3 N/m z direction b. 9.5 N/m z direction c. 6.3 N/m z direction d. 9.5 N/m z direction e. 1.5 N/m z direction For the next two questions, use the following scenario. A rectangular loop of wire (0.10 m by 0.20 m) carries a current of 5.0 A in a counterclockwise direction. The loop is oriented as shown in a uniform magnetic field of 1.5 T. 74. The force acting on the upper 0.10-m side of the loop is a. 1.3 N b N c N d. Zero 75. The force acting on the near 0.20-m side of the loop is a. 1.3 N b N c N d. Zero

13 76. An electron is traveling east with an instantaneous velocity of m/s when it enters a uniform magnetic field of 0.25 T that points X degrees north of east. (Take east as to the right of the paper and north as towards the top of the paper, i.e. both in the plane of the paper.) If the magnitude of the force on the electron is N, then calculate the angle X and whether the electron moves up out of or down into the plane of the page, or otherwise. a. 25 and out of the page b. 65 and into the page c. 25 and into the page d. 65 and out of the page 77. A positively charged particle moves with velocity v along the +x axis. A uniform magnetic field points in the negative z direction. You want to balance the magnetic force with an electric field so that the particle will continue along a straight line. The electric field should be in the a. positive x direction. b. positive z direction. c. negative y direction. d. negative x direction. e. negative z direction. 78. A beam of electrons moving at a speed of m/s is undeflected when it passes through an electric field of 5.0 N/C perpendicular to its path and a magnetic field that is perpendicular to its path and also to that of the electric field. Calculate the strength of the magnetic field. a T b T c T d T e T 79. In a mass spectrometer ions of Ni with mass kg and charge +2e are accelerated through a potential difference of X volts and then deflected in a magnetic field of 0.15 T. If the radius of curvature of the ions is 0.55 m, then calculate the value of the potential difference X. a. 5.7 kv b. 274 kv c. 137 kv d kv 80. At the instant the negatively charged body is at the origin, the magnetic field at point P due to its motion is in the negative x direction. The charged body must be moving a. in the negative z direction. b. in the positive y direction. c. in the positive x direction. d. in the negative y direction. e. in the positive z direction. 81. A 1000-turn solenoid is 50 cm long and has a radius of 2.0 cm. It carries a current of 8.0 A. What is the magnetic field inside the solenoid near its center? a T b T c T d. 1.0 T

14 82. Calculate the number of turns needed in the secondary winding of a transformer to transform a primary voltage of 300 volts down to a secondary voltage of 180 volts, if the primary winding has 1150 turns of wire. a. 540 turns b turns c. 470 turns d. 690 turns 83. A transformer connected to a 120 V ac source has a power output of 2.88 W. If the output current is 120 ma and the primary coil has 330 turns, how many turns of wire are there in the secondary coil? a. 24 turns b. 66 turns c. 330 turns d turns 84. An electron moves counterclockwise in a circular orbit, as shown. The electron generates a magnetic field at the center of its orbit, whose direction is: a. into the page b. out of the page c. to the left d. to the right e. in the direction of the electron s motion 85. When light is incident on a metallic surface, the emitted electrons a. Are called photons. b. Have arbitrarily high energies. c. Have maximum energy that depends on the intensity of the light. d. Are referred to as cathode rays. e. None of these statements are correct. 86. A clean surface of metal will emit electrons when exposed to light. If the colour of the light is changed from red to blue without changing the intensity, the of the ejected electrons will also increase. a. Mass b. Number c. Kinetic energy d. Charge 87. The work function of a metal with a threshold frequency of Hz is: a J b J c J d J 88. The wavelength of a photon is 7.0 x 10-7 m. Its corresponding energy is: a. 1.8 ev b ev c ev d. 2.9 ev 89. A photon has a momentum of N s. The frequency of the photon is: a Hz b Hz c Hz d Hz

15 Mass spectrometers are used in archeological studies to help date ancient artifacts. The relative amounts of carbon-12 and carbon-14 isotopes in a sample of organic material may be used to determine the age of the sample. Carbon-14 is a radioactive isotope that undergoes beta decay and has a half-life of years. 90. The product of the carbon-14 decay is a. N c. Be 7 14 b. O d. C An archeological sample is dated using the carbon-14 dating process and is found to be years old. What percentage of the original carbon-14 remains? a. 25.0% b. 29.3% c. 70.7% d. 75.0% 92. Which of the following is NOT naturally radioactive? a. deuterium oxide (heavy water) b. the sun c. Earth d. the human body 93. Which one of the following statements is TRUE? a. A fission reaction can begin once a U-235 nucleus ejects a slow moving neutron. b. An uncontrollable chain reaction cannot happen without a critical mass of nuclear fuel. c. A moderator is used to speed up neutrons to sustain a chain reaction. d. Fission reactions are used to explode fireworks. 94. An example of a fission reaction is a. b. c. d. 95. The following diagram illustrates some of the main components of a nuclear power generating system. Which one of the following statements is TRUE? a. The fission process occurs in component A. b. The control rods are located in component B. c. The calandria is located in component C. d. Heavy water is located in component D.

16 96. Which of the following is NOT a reason why we use deuterium oxide (heavy water) in CANDU reactors? a. It acts as a moderator to slow down neutrons and sustain a controlled fission chain reaction. b. It acts as a coolant removing heat from the calandria. c. It tends not to absorb neutrons released during fission allowing us to use unenriched uranium as a fuel source. d. It is used as the primary fuel source in the reactor. 97. Which of the following is NOT a safety feature of Canadian CANDU reactors? a. The calandria can be ejected deep underground into a geologically stable rock formation in the Canadian Shield. b. Cadmium control rods can be inserted into the reactor core to absorb neutrons. c. Neutron absorbing liquid can be injected into the reactor core (neutron poison). d. They have concrete reactor containment and a radiation shield.

17 Part 2: Long answer 1. A quarterback must throw a 50.0 m pass to win the game. If it takes the ball takes 1.60 s to reach its maximum height, then what is the initial velocity of the ball? 2. If a 90 kg box is pulled with a 100 N force at 37º above the horizontal, what is the acceleration of the box? 3. What is the centripetal force required to accelerate a 1200 kg car around the entire 75 m radius curve if the car is traveling at 22 m/s. 4. Pete throws a tennis ball horizontally from the top of the 50 m building. Assume that the ball landed 100 m away from the building. a. How long did it take for the ball to reach the ground? b. What was the initial velocity? c. What was the velocity of the ball when it hit the ground?

18 5. According to the Bohr model, a hydrogen atom consists of a proton nucleus and an electron which orbits around the proton. The smallest possible radius of orbit is known as the Bohr radius. Once an electron is in this lowest orbit, it can get no closer to the proton. The electron in this ground state or lowest energy state is held in orbit by an electric force of 8.23 x 10-8 N. a) Calculate the Bohr radius (the average distance between the electron and proton). b) Calculate the centripetal acceleration and the speed of the electron s orbit. 6. A coin is placed on a stereo record, which takes 3 seconds to make a complete revolution. Assume that the coin has a velocity of 5 m/s. a. What is the acceleration of the coin? b. What is the distance from the center of the stereo record to the coin? (numbers are not realistic) 7. Determine the force of gravitational attraction between a 70 kg astronaut and the 20,000kg space shuttle if the astronaut is 15 m from the shuttle.

19 8. The mass of Venus is 4.88 x kg and its radius is 6.07 x 10 6 m. If an instrument package is sent to orbit Venus, at what distance from the surface of Venus will it experience one-eight as much of the force of Venus' gravity as it does on the surface of Venus? Use the following graph of the motion of a 5.0 kg object to answer the next 4 questions. 9. Calculate the displacement between 0 s and 40 s. 10. Calculate the average velocity of the object during the first 20 seconds. 11. Calculate the net force acting on the object from 10 to 20 seconds. 12. Calculate the total distance travelled in 40 s.

20 13. Given the following masses: U-235 = x kg, n = x kg, La-142= x kg, Br-91 = x kg Determine the energy produced in MeV for the fission reaction below: n La + 91 Br + 3 n 92U