THE BIG ONE Physics 30 Review

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1 THE BIG ONE Physics 30 Review Kinematic Equations Statics & Dynamics Equations Area of a triangle A = ½bh Area of a rectangle A = bh Pythagoras c 2 = a 2 + b 2 Law of cosines c 2 = a 2 + b 2 2abcosC Law of sines opp = hyp sinθ adj = hyp cosθ tan θ = opp/adj The acceleration due to gravity is 9.81 m/s 2 towards the surface of the Earth. Centripetal motion Universal gravitation G = 6.67 x Nm 2 /kg 2 Momentum and Impulse Work, Energy and Power Electricity e = x C 1eV = x J k = 9.00 x 10 9 Nm 2 /C 2 Q = Ne ( ) Nuclear Physics 1 u = x kg c = 3.00 x 10 8 m/s 1 J = 6.24 x ev E = mc 2 PART I: Multiple choice Unit 1 and 2 - Choose the best answer.

2 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

3 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 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 7500 N on an elevator weighing 6000 N 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 2

4 16. 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 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?

5 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? 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

6 Part 2: Long answer 29. 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? 30. If a 90 kg box is pulled with a 100 N force at 37º above the horizontal, what is the acceleration of the box? 31. 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. 32. 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?

7 33. 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. (electricity unit) b) Calculate the centripetal acceleration and the speed of the electron s orbit. (mass of electron is 9.11 x kg) 34. 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? 35. 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. 36. 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?

8 Use the following graph of the motion of a 5.0 kg object to answer questions 37, 38, 39, and Calculate the displacement between 0 s and 40 s. 38. Calculate the average velocity of the object during the first 20 seconds. 39. Calculate the net force acting on the object from 10 to 20 seconds. 40. Calculate the total distance travelled in 40 s.

9 THE BIG ONE Part 2 Units 4-6 Multiple choice - Choose the best answer. 1. 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). 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 2. The total kinetic energy just after the collision in question 1 (before starting to compress the spring) is a J b J c J d J 3. What maximum compression of the spring in question 1 occurs when the blocks momentarily stop? a m b m c m d m 4. 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 5. The speed of the block at point P is a m/s b m/s c m/s d m/s

10 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. 6. The spring constant for the recurve bow is a N/m b N/m c. 186 N/m d. 433 N/m 7. 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 8. 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 9. 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 10. 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

11 11. What is the magnitude of the momentum of the baseball FROM QUESTION 10 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. 12. 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 13. 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.

12 14. 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 15. The work done in question 14 is a. 240 J b. 290 J c. 1.2 kj d. 2.2 kj 16. 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 17. 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. The time it takes the rock to contact the water is a s b s c s d s 18. The mechanical energy of the rock in question 17 at the moment it leaves the boys hand is a J b J c. 284 J d J 19. The rock land a horizontal distance away of a. 183 m b m c. 150 m d. 113 m 20. The final speed of the rock in question 17 is a m/s b m/s c. 284 m/s d m/s

13 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. 21. 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 22. 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. 23. 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 24. If the charges in question 24 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

14 Use the following information to answer 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. 25. The total electrical resistance of the laptop computer is a Ω b Ω c Ω d Ω 26. The number of electrons that leave the negative terminal of the battery during the time it is being used would be a x electrons. b x electrons. c x electrons. d x electrons. 27. The total electrical power developed by the laptop computer is a W b W c W d W 28. 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 Use the following diagram to answer questions 29 and Which of the following statements are TRUE? a. The current through R 3 is greater than the current through R 2. b. The voltage drop is greater at R 3 than at R 2 c. The voltage drop across each resistor is the same. d. Each resistor has the same current passing through it. 30. If the total electric current in the circuit is 1.33 A, the resistance of R 1 would be a. 1.8 Ω b. 3.0 Ω c. 6.0 Ω d. 9.0 Ω

15 Use the following diagram to answer questions 38 and Which of the following statements are TRUE? a. The total current could be measured by placing an ammeter at position I. b. An ammeter placed at position III would show the same current as an ammeter placed at position II. c. The voltage drop across R 2 could be measured by placing a voltmeter at position I. d. The voltage drop across R 1, could be measured by placing a voltmeter at position II. 32. The electric current flowing through R 2 is a A b A c A d A 33. Consider the following circuit diagram The total resistance of the circuit is a. 1.3 Ω b. 2.0 Ω c. 6.0 Ω d Ω

16 34. Which of the following is NOT naturally radioactive? a. deuterium oxide (heavy water) b. the sun c. Earth d. the human body 35. 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. 36. An example of a fission reaction is a. b. c. d. 37. The following diagram illustrates some of the main components of a CANDU 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.

17 38. 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. 39. 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. 40. Given the following masses: U-235 = x kg, n = x kg, La-142= x kg, Br-91 = x kg Determine the energy produced in the fission reaction below: