Question

PART IV: Mass vs PE,KE, and total Energy 12. Hypothesis: How would increasing the mass effect the PE, KE and total energy of the system? Hit reset and click energy graph, ruler and timer. Mass of Period kinetic Kinetic Potential Potential Total Pendulum (secs) Energy (cm) Energy (cm) Energy(cm) Energy(cm) Energy (cm) Bob At bottom At top At Bottom At Top .15 kg .30 kg .50 kg .80 kg 13. Was your hypothesis correct? Explain. 14. When the mass increased what other components increased?

Answer 1

Let us first see what happens when the pendulum bob is at top and at bottom.
Part TV Hypothesis: With the increase in total energy of system will also be mass, the PE, KE and increased. Since no graph is given , we assume L is the length of the pendulum, h is the height of the pendulum. O is the angle which the pendulum makes with vertical axis. m= mass of the pendulum bob. go acceleration due to gravity. i ha h(1- cose) Potential energy PE = mgh Kinetic energy KE= t mrez , & is the speed of pendulan. * At top: 0.90, cos 90°= 0 : h=L(1-cos0°) = L ..PE = mgh At top the pendulum is momentarily motionless. so, v=0. K.E. = I mer = 1 m.0 = 0 So, Total energy = PE+KE = mgl. * At bottom : 0-0, copo=1 h=L(1-1)=0 i. Potential energy PE ngle = 0 At the bottom all the energy is kinetic energy = 1 me 2 Total energy - Pe + KE = {moga

The time period of a pendulum depends on the length of the pendulum and does not depend on the mass of the pendulum . bob. Let us say, here the period is I see. The relocity will remain same in all 'cases. Mass of pendulum Perind (see) Kinetic I energy at Kinetic energy at top Potential Potential Total energy at energy at energy Bottom (3) top ( 1 (o) bob bottom (3) (3) 10.15 kg T x0.1500 10.15gh (0.15 gn 0.1572 10.30 kg 1 x 0.30x32 0 10.30gh 10.30gh ***0.30v ² x 0.5000 0 0.50gle 0:50 - 1 x0.500" 0.50 kg 10.6029 ² x 0.80x22 o 0.80 kg 10** WOO -*x0.8992 0.80gh/0,80gh

13. So, the hypothesis is partially true here. See we observed that in every case irrespective of the masses, the kinetic energy at the top of the pendulum is always zero. Again the potential energy at the bottom is zero for each ease. But the kinetic energy at bottom and Potential energy at the top increase with the increase in mass, therefore the total energy also increase. 14. When the mass increased according to newton's second law, love will increase, as F=ma, where mis the mass of to object and a is the acceleration. Kinetic energy and potential energy at any point other than top and bo on will increase. he