Standard Physics Final Exam Review Guide 1) Motion and Kinematics a) Give the equations for the following: - Velocity: - Acceleration: Examples: 1) What is the velocity of an object that moved a distance of 4 m in 2 s? 2) What is the acceleration of a speed boat that goes from 0 to 45 mi/hr in 30 seconds? 3) A car speeds up from a velocity of 8 m/s to a velocity of 12 m/s in 4 seconds. What is the car’s acceleration? b) Free-Fall Equations: - vf = vi + at - d = 1/2at2 - What is the acceleration due to gravity for free falling objects? Examples: 1) Harry drops an egg from the NHS rooftop. How fast is the egg going 3 seconds after he releases it? (remember, from rest, vi = 0) 2) If the egg is falling for 3 seconds, how far has it fallen? 3) A bicyclist is moving at 8 m/s. He speeds up at an acceleration of 4 m/s^2 for 2 seconds. Now what is his velocity? 1 c) Graphing: 1) Sketch a distance vs time graph representing an object that is standing still: 2) Sketch a distance vs time graph representing an object that is moving at a constant velocity: 2) Forces a) Newton’s Laws of Motion. Below are BRIEF descriptions of Newton’s first 3 laws. Make sure that you know how to apply them. - 1st Law: An object in motion stays in motion in a straight line unless acted on by an outside force. - 2nd Law: F = ma - 3rd Law: Equal and opposite forces - What are the units on Force? b) Weight vs Mass: - What is the equation for weight? Examples 1) A car is traveling at a constant speed of 20 mi/hr in a straight line. What is the net force acting on the car? a) Zero c) The net force is upwards b) The net force is to the right d) The net force is down 2) A car is traveling around in a circle with a speed of 35 mi/hr. What can be said about the velocity vs speed of the car? a) Constant speed, changing velocity c) Changing speed, changing velocity b) Changing speed, constant velocity d) Constant speed, constant velocity 2 3) A box of mass 2 kg is moving with an acceleration of 3 m/s^2. What is the Force applied to the box? 4) A boy has a mass of 30 kg. What is its approximate weight on earth? a) 2 N b) 30N c) 100N d) 300N e) 1000N 5) How does the size of the gravitational force with which the earth pulls on a boy compare to the gravitational force with which the boy pulls on the earth. a) The earth pulls with a much larger force b) The boy does not pull on the earth at all c) The forces are equal d) The earth does not pull on the boy at all 6) Draw a Free Body Diagram for an object being pulled by a Force of 2N to the right and a Force of 1N to the left. What is the net force on the object and in which direction? 7) ___________ is a measure of inertia. a) volume b) height c) mass d) color 8) A car crashes into a brick wall – doe the car exert the same force on the wall as the wall does on the car? 3) Momentum and Impulse a) Terms and equations: - What is the equation for momentum? - What is an impulse and what is the equation? - What equation represents change in momentum? 3 - What is conservation of momentum? Questions: 1) An object has a mass of 10 kg and a velocity of 5 m/s. Find its momentum. 2) An object changes its momentum by 4 kg-m/s. What impulse was applied? 3) Tom, driving his 1000 kg car at 30 m/s slows applies to brakes and slows to a stop in 20 seconds. Calculate the force that acts on the car. 4) A .5 kg basketball traveling a 10 m/s strikes a Mars Bar travling towards the basketball at -30 m/s. m = .5 kg vi = 10 m/s a) Calculate the initial momentum of the basketball: a) 0.5 kg m/s b) 10 kg m/s c) 5 kg m/s b) Calculate the initial momentum of the Mars Bar: a) -3 kg m/s b) -300 kg m/s c) -30 kg m/s c) Calculate the total momentum of the intial collision: a) 5 kg m/s b) 2 kg m/s c) -2 kg m/s m = .1 kg vi = -30 m/s d) 20 kg m/s d) -0.1 kg m/s d) 30 kg m/s 5) What is the purpose of padding for a football player? a) Increase the force acting on you while you stop c) Decrease the momentum b) Increase the time it takes for you to stop d) Decrease the impulse 4) Energy a) Mechanical Energy: - Name the two types of mechanical energy we studied. Briefly define each and write the equation: 4 1) 2) - What are the units for energy? b) Conservation of Energy: - What is conservation of energy? c) Work and Energy: - Write the equation for work in terms of Force and Distance: - Work changes the energy of an object! Questions 1) Mary lifts a 15 kg mass from a height of 0m to a height of 5m. a) What type of mechanical energy does the mass gain? b) What is the change in energy of the mass? c) How much work does Mary do? 2) Mary drops her 2 kg book from a height of 10 m. Calculate the potential and kinetic energy of the weight as it falls at each height in the table below: Height (m) Potential Energy (J) Kinetic Energy (J) 0 Total Mech Energy (J) 10 5 0 0 3) What is the Kinetic Energy of an object with a mass of 10 kg moving at a velocity of 8 m/s? 4) A rollercoaster moves along the frictionless surface below. A 5 C B D a) Which point has the largest amount of PE? b) Which point has the largest amount of KE? c) At which point is the car’s velocity the largest? e) How does the Potential Energy at Point A compare to the Kinetic Energy at Point B? 5) Which of the following has the most KE? a) A 1kg mass traveling at 4 m/s b) A 2kg mass traveling at 2 m/s c) A 4kg mass traveling at 1 m/s d) An 8 kg mass traveling at 0.5 m/s e) They are all the same 5) Electricity a) Statics - What does it mean if an object has a net charge? - What are positive charges called? What are negative charges called? b) Circuits: - Draw a circuit showing a battery and 2 lightbulbs in series. What happens to the other bulbs if one goes out? - Draw a circuit showing a battery and 2 lightbulbs in parallel. What is true about the voltage across each branch? What happens to the other bulb if one goes out? - What is the equation for Ohm’s Law? - What is the equation for Power? Questions: 6 1) A 12 volt battery is placed across a lightbulb with a resistance of 4 Ohms. How much current flows in the circuit? 2) How much Power does the light bulb use? 3) Using Ohms Law, how much Current is drawn if a 12 Ohm toaster is plugged into 120 V? a) 10 A c) 14 A b) 15A d) 17 A 4) Two charges attract if they… a) Are both positive b) Are both negative c) One is negative the other is positive 5) What diagram below represents a short circuit? L 1 6) Magnetism 1) Sketch the field lines into the drawing below: N S N S 2) Sketch the field lines into the drawing below: N S S S 3) Likes poles _____________. Opposite poles _____________. 7 4) How is an electromagnet created? 7) Waves Questions: 1) I observe 10 waves every 5 seconds pass by for the wave train below: 2 2 4 For the above wave, what is the : Amplitude, Wavelength, Period, Frequency, Velocity? 2) What happens when two slinky waves collide? a) They collide and destroy each other b) They pass through each other c) They tangle up d) They bounce off 3) When a wave enters a new medium and it bends this is: c) Diffraction c) Refraction d) Reflection 4) What is an example of sound diffracting and then reflecting? a) Hearing the teacher in the hallway and then hearing an echo b) Hearing an echo and then hearing a teacher in the hallway c) Hearing a funny sound under water 5) The color of Visible light changes if the: a) frequency changes b) amplitude changes c) Intensity Changes 6) What characteristic of a sound wave determines the pitch? a) Amplitude b) Frequency c) Wavelength d) Period 7) The speed of a wave depends on: a) The medium b) The color of the wave c) The type of wave d) the frequency 8