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| course_planning:183_projects:f21_week_1_escape_from_ice_station_mcmurdo [2024/01/09 22:40] – hallstein | course_planning:183_projects:f21_week_1_escape_from_ice_station_mcmurdo [2024/01/09 22:56] – hallstein | ||
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| Line 101: | Line 101: | ||
| </ | </ | ||
| <WRAP alert> | <WRAP alert> | ||
| - | **==Steps and Timning: | + | **==Part A Steps and Timning: |
| * 4 quadrants, including the table and representation 20 minutes | * 4 quadrants, including the table and representation 20 minutes | ||
| * Runaway craft - constant velocity 30 minutes | * Runaway craft - constant velocity 30 minutes | ||
| Line 116: | Line 116: | ||
| * Graphing position and velocity of both crafts 75 min | * Graphing position and velocity of both crafts 75 min | ||
| - | == Teaching Points== | + | **== Teaching Points==** |
| * the rescue craft uses the average velocity over each interval | * the rescue craft uses the average velocity over each interval | ||
| * The average velocity used to find its acceleration is the instantaneous velocity at the midpoint in time. | * The average velocity used to find its acceleration is the instantaneous velocity at the midpoint in time. | ||
| Line 125: | Line 125: | ||
| | | ||
| - | ==Part B Timing== | + | Parts A and B are meant to be done on the same day, but in practice half of the folks do not finish part B. It's okay to spend the first part of McMurdo day 2 to complete part B. They need to do this before doing the computational part C. |
| - | * New 4 quadrants 15 min | + | |
| - | * Calculate the speed of the rescue craft at the edge, from $v_{jump}$ 30 min | + | |
| - | * Kinematics $v_{edge}^2 = v_{jump}^2 + 2a\Delta x$ Could use from the beginning point, but the emphasis is on finding the velocity (horizontal) at the edge | + | |
| - | * Or, is time is short, assume $v_{edge}=v_{jump}$ | + | |
| - | * Need to know horizontal v at the edge of the rescue craft to analyze its fall | + | |
| - | * Finding time to fall 45 min | + | |
| - | * Relaize fall time is independent of the (horizontal)velocity at the edge | + | |
| - | * Could have a conversation about what impacts the x component of the velocity | + | |
| - | * Kinematics: $\Delta y = \frac{1}{2} a t_{fall}^2$ to get fall time | + | |
| - | * Finding landing point from the fall time for both crafts: $x=v_{edge}*t_{fall} 60 min | + | |
| - | * Which craft is " | + | |
| - | * Plot x and y vs time; and $v_x$ and $v_y$ vs time | + | |
| - | ==Teaching Points== | + | |
| - | * The diagram can be tricky | + | |
| - | + | ||
| - | Parts A and B are meant to be done on the same day, but in practice half of the folks do not finish part B. It's okay to spend the first part of McMurdo day 2 to complete part B. Thye need to do this before doing the computational part C. | + | |
| - | + | ||
| - | + | ||
| - | + | ||
| - | /* **==Teaching and Discussion Points:==** | + | |
| - | * Relative velocity: If you are here, moving with this velocity what do you observe? | + | |
| - | * How is the river moving relative to the shore? | + | |
| - | * How is the boat moving relative to the shore? | + | |
| - | * If you were on a raft on the river, how would it move? | + | |
| - | * They don't have a measuring tape, but they are told there are two docks on the same side of the river. | + | |
| - | * How do we deal with the distance term? Some may try to pace it off - not very precise | + | |
| - | * This is where working in variables is critical. | + | |
| - | * Realize the distance between the docks is constant, and they can equate two expressions for finding the distance to eliminate this variable. | + | |
| - | * The problem requires some basic algebra that may be a blast from the past | + | |
| - | * Encourage them to think back to algebra class and what they did with two equations and two unknowns. | + | |
| - | * Solving a system of equations! | + | |
| - | */ | + | |
| </ | </ | ||
| Line 228: | Line 196: | ||
| * If students are moving a bit more slowly, it is OK for them to only model the motion of the constant velocity hovercraft on Tuesday and to then consider the constant force hovercraft on Thursday for 15 minutes. | * If students are moving a bit more slowly, it is OK for them to only model the motion of the constant velocity hovercraft on Tuesday and to then consider the constant force hovercraft on Thursday for 15 minutes. | ||
| </ | </ | ||
| + | <WRAP alert> | ||
| + | |||
| + | **==Part B Steps & Timing==** | ||
| + | * New 4 quadrants 15 min | ||
| + | * Calculate the speed of the rescue craft at the edge, from $v_{jump}$ 30 min | ||
| + | * Kinematics $v_{edge}^2 = v_{jump}^2 + 2a\Delta x$ Could use from the beginning point, but the emphasis is on finding the velocity (horizontal) at the edge | ||
| + | * Or, is time is short, assume $v_{edge}=v_{jump}$ | ||
| + | * Need to know horizontal v at the edge of the rescue craft to analyze its fall | ||
| + | * Finding time to fall 45 min | ||
| + | * Relaize fall time is independent of the (horizontal)velocity at the edge | ||
| + | * Could have a conversation about what impacts the x component of the velocity | ||
| + | * Kinematics: $\Delta y = \frac{1}{2} a t_{fall}^2$ to get fall time | ||
| + | * Finding landing point from the fall time for both crafts: $x=v_{edge}*t_{fall} 60 min | ||
| + | * Which craft is " | ||
| + | * Plot x and y vs time; and $v_x$ and $v_y$ vs time | ||
| + | ==Teaching Points== | ||
| + | * The diagram can be tricky | ||
| + | |||
| + | Parts A and B are meant to be done on the same day, but in practice half of the folks do not finish part B. It's okay to spend the first part of McMurdo day 2 to complete part B. Thye need to do this before doing the computational part C. | ||
| + | </ | ||
| + | |||
| + | |||
| <WRAP info> | <WRAP info> | ||
| ==Common Difficulties== | ==Common Difficulties== | ||