Students will review their knowledge of tension and focus on tensile loads and failure caused by them.
Students learn the basics of the electromagnetic spectrum and how various types of electromagnetic waves are related in terms of wavelength and energy. In addition, they are introduced to the various types of waves that make up the electromagnetic spectrum including, radio waves, ultraviolet waves, visible light and infrared waves. These topics help inform students before they turn to designing solutions to an overarching engineering challenge question.
Based on what they have already learned about friction, students formulate hypotheses concerning the effects of weight and contact area on the amount of friction between two surfaces. In the Associated Activities (Does Weight Matter? and Does Area Matter?), students design and conduct simple experiments to test their hypotheses, using procedures similar to those used in the previous lesson (Discovering Friction). An analysis of their data will reveal the importance of weight to normal friction (the friction that occurs as a result of surface roughness) and the importance of surface area to the friction that occurs between smooth surfaces due to molecular attraction. Based on their data, students will also be able to calculate coefficients of friction for the materials tested, and compare these to published values for various materials.
All of us have felt sick at some point in our lives. Many times, we find ourselves asking, "What is the quickest way that I can start to feel better?" During this two-lesson unit, students study that question and determine which form of medicine delivery (pill, liquid, injection/shot) offers the fastest relief. This challenge question serves as a real-world context for learning all about flow rates. Students study how long various prescription methods take to introduce chemicals into our blood streams, as well as use flow rate to determine how increasing a person's heart rate can theoretically make medicines work more quickly. Students are introduced to engineering devices that simulate what occurs during the distribution of antibiotic cells in the body.
Working individually or in groups, students explore the concept of stress (compression) through physical experience and math. They discover why it hurts more to poke themselves with mechanical pencil lead than with an eraser. Then they prove why this is so by using the basic equation for stress and applying the concepts to real engineering problems.
This is an exploratory activity where students in small groups discover the relationship between the force of resistance, the force of effort, and placement of the fulcrum in a first class lever.
Students are introduced to the important concept of density with a focus is on the more easily understood densities of solids. Students use different methods to determine the densities of solid objects, including water displacement to determine volumes of irregularly-shaped objects. By comparing densities of various solids to the density of water, and by considering the behavior of different solids when placed in water, students conclude that ordinarily, objects with densities greater than water sink, while those with densities less than water float. Then they explore the principle of buoyancy, and through further experimentation arrive at Archimedes' principle that a floating object displaces a mass of water equal to its own mass. Students may be surprised to discover that a floating object displaces more water than a sinking object of the same volume.
This lesson introduces students to the important concept of density. The focus is on the more easily understood densities of solids, but students can also explore the densities of liquids and gases. Students devise methods to determine the densities of solid objects, including the method of water displacement to determine volumes of irregularly-shaped objects. By comparing densities of various solids to the density of water, and by considering the behavior of different solids when placed in water, students conclude that ordinarily, objects with densities greater than water will sink, while those with densities less than water will float. Density is an important material property for engineers to understand.
This is a classroom lab where students will explore the concept of density by investigating how various solids and liquids interact.
Students discover fluid dynamics related to buoyancy through experimentation and optional photography. Using one set of fluids, they make light fluids rise through denser fluids. Using another set, they make dense fluids sink through a lighter fluid. In both cases, they see and record beautiful fluid motion. Activities are also suitable as class demonstrations. The natural beauty of fluid flow opens the door to seeing the beauty of physics in general.
Students learn about the fundamental concepts important to fluid power, which includes both pneumatic (gas) and hydraulic (liquid) systems. Both systems contain four basic components: reservoir/receiver, pump/compressor, valve, cylinder. Students learn background information about fluid power—both pneumatic and hydraulic systems—including everyday applications in our world (bulldozers, front-end loaders, excavators, chair height lever adjustors, door closer dampers, dental drills, vehicle brakes) and related natural laws. After a few simple teacher demos, they learn about the four components in all fluid power systems, watch two 26-minute online videos about fluid power, complete a crossword puzzle of fluid power terms, and conduct a task card exercise. This prepares them to conduct the associated hands-on activity, using the Portable Fluid Power Demonstrator (teacher-prepared kits) to learn more about the properties of gases and liquids in addition to how forces are transmitted and multiplied within these systems.
The egg-drop activity is designed to help students develop a deeper understanding of the force created by wind resistance and how it interacts with the force due to Gravity. Students will note how surface area affects the resistance of a falling object as Gravity works on it. Students will record and share observations and questions regarding the experiment.
In the first of two lessons of this curricular unit, students are introduced to the concept of friction as a force that impedes motion when two surfaces are in contact. Student teams use spring scales to drag objects, such as a ceramic coffee cup, along a table top or the floor, measuring the frictional force that exists between the moving object and the surface it slides on. By modifying the bottom surface of the object, students find out what kinds of surfaces generate more or less friction. They also discover that both static and kinetic friction are involved when an object initially at rest is caused to slide across a surface. In the second lesson of the unit, students design and conduct experiments to determine the effects of weight and surface area on friction. They discover that weight affects normal friction (the friction that results from surface roughness), but for very smooth surfaces, the friction due to molecular attraction is affected by contact area.
Use this activity to explore forces acting on objects, practice graphing experimental data, and introduce the algebra concepts of slope and intercept of a line. A wooden 2 x 4 beam is set on top of two scales. Students learn how to conduct an experiment by applying loads at different locations along the beam, recording the exact position of the applied load and the reaction forces measured by the scales at each end of the beam. In addition, students analyze the experiment data with the use of a chart and a table, and model/graph linear equations to describe relationships between independent and dependent variables.
Students conduct several simple lab activities to learn about the five fundamental load types that can act on structures: tension, compression, shear, bending and torsion. In this activity, students play the role of molecules in a beam that is subject to various loading schemes.
Students learn about the Foucault pendulum an engineering tool used to demonstrate and measure the Earth's rotation. Student groups create small experimental versions, each comprised of a pendulum and a video camera mounted on a rotating platform actuated by a LEGO MINDSTORMS(TM) NXT motor. When the platform is fixed, the pendulum motion forms a line, as observed in the recorded video. When the rotating, the pendulum's motion is observed as a set of spirals with a common center. Observing the patterns that the pendulum bob makes when the platform is rotating provides insight as to how a full-size Foucault pendulum operates. It helps students understand some of the physical phenomena induced by the Earth's rotation, as well as the tricky concept of how the perception of movement varies, depending on one's frame of reference.
The lesson will first explore the concept of current in electrical circuits. Current will be defined as the flow of electrons. Photovoltaic (PV) cell properties will then be introduced. Generally constructed of silicon, photovoltaic cells contain a large number of electrons BUT they can be thought of as "frozen" in their natural state. A source of energy is required to "free" these electrons if we wish to create current. Light from the sun provides this energy. This will lead to the principle of "Conservation of Energy." Finally, with a basic understanding of the circuits through Ohm's law, students will see how the energy from the sun can be used to power everyday items, including vehicles. This lesson utilizes the engineering design activity of building a solar car to help students learn these concepts.
Students are introduced to the multidisciplinary field of material science. Through a class demo and PowerPoint® presentation, they learn the basic classes of materials (metals, ceramics, polymers, composites) and how they differ from one another, considering concepts such as stress, strain, ductile, brittle, deformation and fracture. Practical examples help students understand how the materials are applied, and further information about specific research illustrates how materials and material science are useful in space exploration. A worksheet and quiz are provided.
While we know air exists around us all the time, we usually do not notice the air pressure. During this activity, students use Bernoulli's principle to manipulate air pressure so its influence can be seen on the objects around us.
Students use hot glue gun sticks to learn about the forces of tension, compression and torsion.