This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: MASSACHUSETTS INSTITUTE OF TECHNOLOGY Physics Department Physics 8.01 Fall Term 2010 Experiment 03: Work and Energy Purpose of the Experiment: In this experiment you allow a cart to roll down an inclined ramp and run into a spring that is attached to a force sensor. You will measure the position of the cart and the force exerted on it by the spring while they are in contact. It is a real world experiment, which means that there are non-conservative forces: friction as the cart rolls up and down the track, and dissipation (internal friction?) in the spring. The goals of the experiment are: To investigate experimentally the workkinetic energy theorem, how potential energy in a gravity field converts to kinetic energy which is then converted into the potential energy of a compressed spring. To observe and quantify the effect of non-conservative forces and estimate the work done by these forces at various stages of the carts motion up and down the ramp. Experimental Materials: Logger Lite Software Vernier LabPro Interface PASCO cart with 250 gm weights PASCO track Vernier Motion Detector Vernier Dual-Range Force Sensor with spring and securing device small 2 4 block Setting Up the Experiment: Refer to the photo to the right and the figure at the top of the next page. The motion detector should be placed at one end of the track, as in the photo at the right. The motion sensor works best if it is aimed slightly above the center of the cart rather than pointing directly at it. (That reduces the effect of sound waves that bounce off the track before hitting the cart.) The slide switch on top of the motion sensor should be set to the narrow beam position. Place the force sensor at the other end of the track as shown in following figure. 1 Raise the track by placing a short piece of 2 4 under the motion sensor where it clips onto the track, as you can see in the photo to the right. This should raise the end of the track about 4.2cm above the table; as the track is 122cm long, you can calculate the slope = 1 . 97 and sin = 0 . 0344. y x 4.2 cm Place a cart on the track with the end having the Velcro TM patches facing the motion sensor. Put two 250gm weights in the cart, which will bring its total mass to 750gm. (The extra mass reduces vibrations and gives less noisy measurements.) Place the cart about 30cm up the track from the force sensor and release it. It will roll down the track, bounce most of the way back up, and repeat that several times. You will notice the track slides when the cart runs into the spring; this is an example of conservation of momentum. To prevent the track from sliding, place your thumb on the end of the track resting on the table and press it firmly against the table. If you dont do this, when the cart runs into the spring some of its kinetic energy will be dissipated by friction of the track on the tablewhich will introduce an unknown error in your analysis.an unknown error in your analysis....
View Full Document