Kinematics Assignments

Starter: covert these measures KUS objectives BAT investigate real life models BAT make sensible assumptions BAT analyse the problem and interpret/ validate Starter: covert these measures 32 m/s to km/h 70 mph to km/h 2

1 SCOUTS PACE Scouts pace consists of alternatively walking and running an equal number of steps e.g. walking 40, running 40, walking 40 etc. This enables large distances to be covered   Task: Set up a model to Investigate how long it would take a Scout to cover 2 km What is the average speed of this Scout? Assumptions: Each scouts pace is 1 m Assume a steady walking pace of 2 ms-1 Assume a steady running pace of 3 ms-1 Evaluate: Test the assumptions and conclusions you have made by finding the time you would take to cover 2 km at scouts pace

2 FIRE DRILL Fire regulations say that, in an emergency it must be possible to evacuate the main hall in a given length of time. The way people leave has a marked effect on the speed and efficiency of an evacuation. The instinctive reaction is for everyone to crowd round the door and push their way through. A more sensible approach might be for people to stand back a little then walk briskly through the door in single file   Task: Set up a model to Investigate how the time needed to evacuate 100 people through one door depends on the distance between each person and the next. Draw diagrams Choose variables and assign constant values Interpret your solution Evaluate: Write a paragraph to discuss the validity of your solution in the light of limitations of your model. What changes or refinements would you make to your model?

3 GETTING IN THE SWIM Task: A group of swimmers are following a training schedule that requires them to dive into the water and swim one length of a pool. This must be repea6ted 20 times. The have been allocated one lane of the pool only and for safety’s sake must all swim in the same direction in single file |Half the swimmers say it will be quickest always to swim in the same direction, climbing out and walking back to the other end to re-join the queue. The others want to climb out at the end of each length, wait until all swimmers have completed the length then set off one by one in the opposite direction Task: Choose the method you prefer and investigate the time it is likely to take before all the swimmers have completed the session Draw diagrams, make hypotheses Choose variables and assign constant values Interpret your solution Evaluate: Test the assumptions and conclusions you have made by finding the time you would take to cover 2 km at scouts pace

4 Stop and Go Traffic Lights A set of temporary traffic lights restricts traffic on a busy road to one lane. There is a queue in both directions. The speed limit along the single lane is 20 ms-1 and the cars are expected to obey the two second rule which states that the gap between two cars should be the same as the distance the second car will travel in two seconds. The police need to set the lights so that the queues in both directions are kept as short as possible   Task: What time sequence should they use for the red and green lights at each end? Draw diagrams Choose variables and assign constant values Interpret your solution Evaluate: Write a paragraph to discuss the validity of your solution in the light of limitations of your model. What changes or refinements would you make to your model?

5 Walking to work A simplified distance time (s - t) graph of a teachers walk to work one morning is given below s (m) t (mins) 0 1 2 3 4 5 6 7 8 Task 1a: Explain the shape of the graph by describing what might have happened at each stage of the journey. Sketch a Velocity time (v – t) graph for this journey Task 1b: Sketch an estimate of the distance time graph for your journey to school or work Describe how various features of the journey are represented on the graph

6 Overtaking The Highway code states that on an open road, in good conditions, a two second gap between cars should be sufficient.   Task: Find the passing distance needed for a car to safely overtake a lorry moving at a steady speed of 50 mph. Sketch a distance time graph (and velocity time graph) showing the car and lorry as the overtake happens Extension: Consider the case where the car slows down to match the lorry’s speed then speeds up to overtake Draw diagrams Choose variables and assign constant values Interpret your solution Evaluate: Test the assumptions and conclusions you have made by finding the time you would take to cover 2 km at scouts pace

remember for next lesson …. KINEMATICS 1C KUS objectives 1 investigate real life models 2 make sensible assumptions 3 analyse the problem and interpret/ validate One thing I will do For the next lesson …. One thing I need to remember for next lesson …. One thing I understood well is …. Plenary pyramid

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