A bicycle racer is going downhill at 13.0 m/s when, to his horror, one of his 2.36-kg wheels comes off when he is 67.0 m above the foot of the hill. We can model the wheel as a thin-walled cylinder 85.0 cm in diameter and neglect the small mass of the spokes. Required:
a. How fast is the wheel moving when it reaches the foot of the hill if it rolled without slipping all the way down?
b. How much total kinetic energy does the wheel have when it reaches the bottom of the hill?

Part f - example: finding two forces (part i) two dimensional dynamics often involves solving for two unknown quantities in two separate equations describing the total force. the block in (figure 1) has a mass m=10kg and is being pulled by a force f on a table with coefficient of static friction îľs=0.3. four forces act on it: the applied force f (directed î¸=30â above the horizontal). the force of gravity fg=mg (directly down, where g=9.8m/s2). the normal force n (directly up). the force of static friction fs (directly left, opposing any potential motion). if we want to find the size of the force necessary to just barely overcome static friction (in which case fs=îľsn), we use the condition that the sum of the forces in both directions must be 0. using some basic trigonometry, we can write this condition out for the forces in both the horizontal and vertical directions, respectively, as: fcosî¸â’îľsn=0 fsinî¸+nâ’mg=0 in order to find the magnitude of force f, we have to solve a system of two equations with both f and the normal force n unknown. use the methods we have learned to find an expression for f in terms of m, g, î¸, and îľs (no n).

The table below shows the acceleration of gravity on different bodies in the solar system. on which body would a 10 kg lamp has the most gravitational potential energy when lifted to a height of 2 m? a. earth b. mars c. neptune d. uranus

Question 1 what is amperage? is the rate of doing work. is the rate of flow of protons in electric current. represents the amount of pressure behind electron flow. is the rate of flow of electrons in electric current. 2 points question 2 what is voltage? is the rate of doing power. represents the amount of pressure behind electron flow. is the rate of doing work. is the rate of flow of electrons in electric current. 2 points question 3 what is power? is the rate of flow of protons in electric current. is the rate of flow of electrons in electric current. is the rate of doing work. represents the amount of pressure behind electron flow. 2 points question 4 if we multiply volts times amps we get what? power circuit work current 2 points question 5 what are two ways alternating currents are similiar? in both ac and dc electrons flow in the same pattern. in both ac and dc, the flow of electrons changes directions back and forth. both ac and dc are only possible in certain materials with atoms that will allow electron flow. both ac and dc involve the flow of electrons. 4 points question 6 how does the flow of electrons flow in an alternating current? the flow of electrons is always slower in an alternating current than within a direct current. the flow of electrons is not constant and forward; it changes direction back and forth. electrons flow from from a higher affinity to that of a lower affinity. electron flow is constant and only in a forward direction. 2 points question 7 what is the flow like in a direct current? the flow of electrons is not constant and forward; it changes direction back and forth. the flow of electrons is constant and only in a forward direction. the flow of electrons go from a higher affinity to a lower affinity. the flow of electrons are always faster in a direct current. 2 points question 8 how is an electric current able to flow? electrons flow from the higher affinity to lower affinity and electrical current is generated. protons flow from the higher affinity to lower affinity and electrical current is generated. the movement of protons from one atom to another leads to an electric charge. the movement of electrons from one atom to another atom in a line results in a flow of electric current. 2 points question 9 how do electrons move from the two different types of metal in a battery? protons flow from the metal with the lower affinity to the metal with higher affinity and electrical current is generated. electrons flow from the metal with the lower affinity to the metal with higher affinity and electrical current is generated. electrons flow from the metal with the higher affinity to the metal with lower affinity and electrical current is generated. protons flow from the metal with the higher affinity to the metal with lower affinity and electrical current is generated.