Theory of Springs

       a i  iilii lii i liiiLast Lecture Friction Today Springs Important Concepts The magnitude of the spring force depends linearly on the distance the spring is stretched or compressed. The direction of the force is inward at both ends for stretched spring and outward at both ends for a compressed spring. Important Remnders Pset # 4 due here tomorrow at 10am. Next Masterng Physcs deadne s next Monday. Next In-Cass Experment s next Tuesday. Next Pset due next Frday. Want to make 8.01L better? Vounteers needed for a student advsory board, f you are nterested. A better course and free food! ii iiili!   iili |F|(l−l0)  ibilitii −’ “l”, l0   ’t “li” i ill’li iillel ii iiiii !F=!k!l!!l0() F=kl!l0()keff=k1+k2+...1keff=1k1+1k2+...Propertes of Sprng Force The drecton s aways unambguousIn for stretched spring, out for compressed spring. The magntude s aways unambguous! =kTwo posses for confuson. Double negative: Using F=kx where it doesnt belong Forgetting the unstretched engthSummary Dondoube negatveyour sprng force. Thnk carefuy about the geometry. Dont forget the unstretched ength of the sprng. Two or more sprngs n parahave an effectve sprng constant of Two or more sprngs n seres have an effectve sprng constant of 1