Physical Science Final Exam
Type your answers in the blank for each question. Do NOT use the internet – use ONLY the textbook to create solutions in your own words.
1. A car that increases its speed from 20 km/h to 100 km/h undergoes ____________________ acceleration.
2. It usually takes more force to start an object sliding than it does to keep an object sliding because static friction is usually ____________________ than sliding friction.
3. As an object’s temperature increases, the ____________________ at which it radiates energy increases.
4. Using a hammer to drive a nail, it is the reaction force that brings the motion of the hammer to a stop but the _______________ that drives the nail into the wood.
5. The region where a magnet’s force is strongest is at the_________________________.
6. When a person plucks a guitar string, the number of half wavelengths that fit into the length of the string determines the ____________________ of the sound produced.
7. The energy source used to produce most of the electrical energy in the United States is ____________________.
8. The magnetic field lines of a bar magnet begin near the magnet’s ____________________.
9. In a closed system, the loss of momentum of one object ____________________ the gain in momentum of another object.
10. The law of reflection states that the angle of reflection is equal to the angle of ____________________.
Type your answers in the space below each question. Do NOT use the internet – use ONLY the textbook to create solutions in your own words. To get full credit for any math problem, you must show work and final units.
11. How much time will it take a car travelling at 88 km/hr (55 mi/hr) to travel 500km? Show work for credit and include final units.
12. During a race, a runner runs at a speed of 6 m/s. 2 seconds later, she is running at a speed of 10 m/s. What is the runner’s acceleration? Show your work.
13. Look at the graph below measuring the speed of a truck and answer the following 2 questions:
a) If the graph represents speed, what is measured on the x and y axes? You need to specifically identify which axis is which.
b) Based on what the y axis measures, explain the motion of the truck represented by the graph from point 2 to 6.
14. If you push a 900N refrigerator with the same force as you lift a 40N dumbbell, the dumbbell will move faster. According to Chapter 12, which of Newton’s laws is this an example of? Explain how you know.
15. How does the strength of an electromagnet depend on the current and the number of turns in the coil?
16. Identify two types of nuclear reactions in which the equation E = mc2 applies.
Use the following picture to answer questions #17 and #18. Consider that after the snowboarder starts down from the hill from point A, she travels all the way to the end of the path.
17. Standing still at the top of the hill at point A, what kind of energy (potential and/or kinetic) would the snowboarder have? How do you know?
18. Explain the energy conversion from point C to point B. Make sure to include a description of both kinetic and potential energy.
19. A small dog is trained to jump straight up a distance of 1.2 m. How much kinetic energy does the 7.2-kg dog need to jump this high? (The acceleration due to gravity is 9.8 m/s2.) Show your work for credit.
20. As 390 g of hot milk cools in a mug, it transfers 30,000 J of heat to the environment. What is the temperature change of the milk? The specific heat of milk is 3.9 J/g·°C. Show your work for credit.