Question

Lab 7 Analysis

ANALYSIS: 1. Use Logger Pro and graph the energies as a function of time. Please show all energies on the same graph. 2. Inspect your kinetic energy vs. time graph for the toss of the ball. Explain its shape. 3. Inspect your gravitational potential energy vs. time graph for the free-fall flight of the ball. Explain its shape. 4. Inspect your Total energy vs. time graph for the free-fall flight of the ball. Explain its shape. 5. What do you conclude from this graph about the total energy of the ball as it moved up and down in free fall? Does the total energy remain constant? Should the total energy remain constant? Why? If it does not, what sources of extra energy are there or where could the missing energy have gone? For PHY2048 only: 6. Take the derivative with respect to time of the equations describing the energies. Explain their meanings. 7. Calculate the kinetic energy of the basketball for one complete toss, graph it and explain every portion of the graph.

Answer 1

Kinetic energy vs time graph Kinetic energy () 3.25 3.3 3.35 3.4 3.5 3.55 3.6 3.65 3.45 Time (s)

Time vs kinetic energy is parabolic in shape.. When a basket ball is thrown up an initial Velosity is imparted on it. This gives the ball a kinetic energy mo? As the ball rises its velosity decreas 4 reaches minimum value at maximum height point where voo & then again increases as its velosity increases 3 Potential energy vs time graph also following Parabolic in shape but opposite as previous. O It's energy is mgh. As ball is thrown heigh increases, Rotential energy increases, reaches maximum value of then again decreases. 4 Total energy almost remains Constant around 5.8 J. As it is experimental value, there are some resistance like air resistance, So total energy is varying but ideally it should be constant. I total energy almost remains Constant. Since it. is experimental value there should be some variation That is present here also As the ball moving up or down total energy should remains Constants when it moves up potential energy increases as its height is increases & kinetic energy decreases as velosity decreases. So total energy remains Constant.

Should remains loss will occure. Istance some energy (6 P. E a migh m-mass, vertical height Ideally total energy energy Should remains a Constant if there are not any viscous or resistive force. Here some variation is ne variation is present. These present. These variation may arrises due to air resistance. Because of air resistance some ene P. E = mgh m-mass, g-gravitational acceleration dre at - mg dh means as heigh changes with time potential energy changes. enersy k. E= mor dKE at = 2 * 2 mu do muda as velosity changes with time kinectic energy will also changes with time when do so, kinetic energy reaches maximum value I KIE= 12mu Basket ball thrown upward with a velosity. As velosity Aecreases as particle moving upward against gravity sol K.E decreases & reaches minima at maximum height of basket ball, since at that pant velosity is zero K. E

from maximum height when it falls down ward its speed is again increasing, so kinetic energy is also increasing It reaches maximum when it exactly falls on the ground.