In this experiment we sent carts down an incline ramp and used photogates to mea

Question

In this experiment we sent carts down an incline ramp and used photogates to measure the times that the cart passed by. The goal is to look at kinetic energy and work done by gravity on an inclined plane. We will find theoretical work (W = F x D) and the actual work represented by the change in kinetic energy of the cart (K = 1/2 mv ^2) then compare the two values.

Ok here is my data:
Setup #1 Table 1. Measurements
Mass of Cart .63167 kg
Angle of Incline 20 degrees
Height of Ramp 33 cm
Length of Ramp 90.5 cm
Distance of black mark on cart 2.54 cm
Distance between light sensors 82 cm

Setup #1 Table 2. Trial data
Trial 1 2 3 4 5
Time 1 (s) 0.0279 .0306 .0324 .0305 .0288
Time 2 (s) .0108 .0110 .0110 .0109 .0109

Please help me find the theoretical and actual work of this run.

Explanation / Answer

OK, the car sped up so it took about 0.03s to go an inch at the top and about .011 to go an inch at the bottom. We can find the average speed for this inch at the top and the average speed for this inch at the bottom (yes, the speed will change slightly over the inch, but only slightly) Distance = rate times time = d = rt r = d/t r top = 2.54cm/(AVERAGEtime1) = .0254m/0.03s = 0.846 m/s r bottom = 2.54/(AVERAGEtime2) = .0254m/0.011s = 2.33 m/s Change in actual KE = 1/2m(V2^2 - V1^2) = 1/2*0.63167kg(5.41-.715)m^2/s^2 = 1.483 J Theoretical work F*d = mgsin(theta)*d = 0.63167kg*9.8m/s^2*sin(20)*0.82m = 1.736 J Theoretical is more than actual. We didn't get to the theoretical speed, so we have less work done on the car by gravity. Friction and wind resistance are the likely culprits.

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.