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# Michael D. Eisner College of Education

SIMULATED EXPERIMENTS

646-4 Simulated Experiments

(1) Simiulated Internet-Based Experiments

Althought computer simulations are not adequate substitutes for traditional hands-on experiments, they may be useful enhancements. Select an on-line simulation such as one of the following and write a brief lesson plan showing how this simulation can be integrated with hands-on activities to imrprove instruction.

(2) Physics Experiments (Fun Physics; Interactive Physics) Knowledge Revolution:

(a) Basketball: Change the velocity of the ball or the elasticity of the backboard to sink the shot in order to make the basket. Include a printout printout showing that you made the basket.

(b) Earthquakes: The effects of an earthquake can be studied using the earthquake file. Adjust the number of springs and/or the spring constants to determine the conditions necessary to topple the third story of the "building". Include a printout showing the toppling of the third story. Study the effect of lax building codes (insufficient bolting of objects together) on a structure by repeating the experiment with low coefficients of friction among the top 4 stories. Briefly summarize your findings.

(c) Rocket stabilization: Run the Lunar Lander file and note that an off-center force created by a shifting payload can cause a crash. Is a shifting payload more dangerous when taking off from the Moon or from the Earth? Explain. Is the effect more serious if the mass of the shifting payload is large or small? Real rockets have engines that adjust the direction of their thrust during flight to counteract such problems. Apply an additional force to the lunar lander so that it can lift off successfully from the Earth with a 400 kg shifting payload. Include a printout of your successful launch.

(d) Shooting gallery: A target is dropped the instant a gun is fired. Should the marksman aim at the target, above the target, or below the target in order to intercept it as it falls? Use Fun Physics or Interactive Physics to design an experiment that answers this question. With tracking and component vectors on, run the experiment, and stop it at the moment the projectile intercepts the target. Include a printout of this actual collision.

(e) Falling Objects Galielo said that objects accelerate to the earth at the same rate, regardless of mass. Design an experiment using Fun Physics to test this. Compare the velocity of impact of these objects with the velocity of similar objects dropped from the same height on the moon. Report your findings.

(f) Factors affecting the period of a pendulum. Is the period of a pendulum dependent upon its length, mass, or both? Design an experiment in Fun Physics to answer this question. Compare your results with real pendulums in the labs. Include a printout of your experimental design.

(g) Simple Harmonic motion. Do a pendulum or a spring exhibit simple harmonic motion? Graph the velocity (vx or vy) or position (x or y) or a pendulum to find out.

(h) Velocity and acceleration: Design an experiment that monitors the vertical position, velocity, and acceleration of a projectile. Include a printout similar to the figure below. What is the relationship between velocity, and acceleration?

(i) Collisions: Perform the following experiment using real spheres, and then test it using Fun Physics. Include a printout of your experimental design as well as a written summary of your findings.

Part 3: Biology Experiments Logal

(a) Effect of Drought on Plant Productivity: How does drought affect photosynthesis? Complete the following data table and then describe how drought affects the productivity of crops. Plot your data as a scatterplot with Excel or other graphing program.

(b) Why are Leaves Green? Perform a study of the influence of the wavelength of light on the rate of photosynthesis by collecting data to complete the following table. Use a spreadsheet program to create a graph of your data and include this graph in your portfolio. On the basis of the data you collected, why do you believe that most leaves appear green? Plot your data as a scatterplot with Excel or other graphing program.

(c) Nuclear Winter: What effect would nuclear winter have upon plant productivity? Scientists have warned that the detonation of a large number of nuclear warheads would put so much particulate matter in the atmosphere that the light intensity might drop to approximately half its normal level in many areas. Assuming that a 50% reduction in light intensity is accompanied by a 20�C drop in temperature, determine the relative change in photosynthetic activity. Include a printout of your model window with a description of your findings.

(d) Your own experiment: Design and conduct a simple experiment using one of the following programs: (Cardiovascular system; Population Biology; Genetics). Include a description of your experiment and a printout of your model window.