Experiment #4: Collisions Ball Bearing Collision: The following masses were weighed on digital scale that reads to two decimal places. Mass of 10 small balls 2.54 grams Mass of 10 large balls 4.41 grams *In the experiment you weigh the mass of 10 balls, but you enter the mass of one ball in the spreadsheet AirTrack Collision: The following times were measured with a digital timer that measures to 3 decimal places in seconds. Time 1 - 0.224 seconds Time 2 - 0.695 seconds The following masses were weighed on a scale that reads to two decimal places. Mass of cart with sail 103.95 grams Mass of cart without sail 102.94 grams The following length was measured with a Vernier caliper. Length of sail - 115.00 +/- 0.05 mm Legend You can enter data in orange boxes. Please enter numbers in decimal format. For example, use 0.001, NOT 101-3 Values in green boxes will be calculated automatically when you have entered all the required data in the orange boxes. Values in blue boxes cannot be changed and indicate names of variables and/or units to be used. Small Ball Large Ball At= seconds m= grams m= grams uncertainty m= grams uncertainty m= grams Trail of Dots X-position (cm) X-uncertainty (cm) Y-position (cm) Y-uncertainty (cm) n AX (cm) Uncertainty AX (cm) AY (cm) Uncertainty AY (cm) Projectile Before Dot 1 0 0 Dot 2 Projectile After Dot 1 0 0 0 Dot 2 Target After Dot 1 0 0 0 0 Dot 2Dot 2 Trail of Dots X-velocity (cm/s) Incert X-vel (cm/) Y-Velocity (cm/s) |Uncert Y-vel (cm/s) V2 (cm2/s2) Uncert V2 Projectile Before #DIV/O! #DIV/O! #DIV/O! #DIV/O! Projectile After #DIV/O! #DIV/O! #DIV/O! #DIV/O! #DIV/O! #DIV/O! Target After #DIV/O! #DIV/O! #DIV/O! #DIV/O! #DIV/O! #DIV/O! Before Collision X-momentum (gcm/s) incert X-mo (gcm/Y-momentum (gcm/s) Uncert Y-mo (gcm/s)|KE (gcm2/s2) Uncert KE (gcm2/s?) Projectile #DIV/O! #DIV/O! #DIV/O! #DIV/O! Target After Collision Projectile #DIV/O! #DIV/O! #DIV/O! #DIV/O! #DIV/O! #DIV/O! Target #DIV/O! #DIV/O! #DIV/O! #DIV/O! #DIV/O! #DIV/O! Totals: (with correct sig figs) Total Total Total Total Total Total X-momentum (gcm/s) incert X-mo (gcm/)Y-momentum (gcm/s) Uncert Y-mo (gcm/s) KE (gcm2/s2) Uncert KE (gcm2/s?) Before Collision After CollisionTotals: (with correct gig figs) Total Total Before Collision After Collision Is this collision considered to be isolated or norr isolated? (conservation of momentum) Is this collision considered to be elastic or inelastic? [conservation of kinetic energg) X-momentum What role did uncertainties playr in determining the above two answers? For the above answers that were conserved, were they perfectly conserved? If not. why.) When choosing dots from the picture. is it better to choose NW) dots closely spaced together or further part? Explain. Air Track Collision: Cart With Sail Cart Without Sail Time 1= seconds mass= grams mass= gran Uncert Time 1= seconds Uncert mass= grams Uncert mass= gran Time 2= seconds Length of Sail Uncert Time 2= seconds L= cm Uncert L= cm Before Collision Uncert Before Collision Uncert Velocity= #DIV/O! #DIV/O! cm/s Rewrite Table on Left Velocity= cm/s Momentum= #DIV/O! #DIV/O! gcm/s With Correct Momentum= gcm/s KE= #DIV/O! #DIV/O! gcm2/s2 Sig Figs KE= gcm2/$2 After Collision Uncert After Collision Velocity= #DIV/O! #DIV/O! cm/s Velocity= cm/s Momentum= #DIV/O! #DIV/O! gcm/s Momentum= gcm/s KE= #DIV/O! #DIV/O! gcm2/s2 KE= gcm2/s2Momentum = #I #I Is this collision considered to be isolated or non- isolated? (conservation of momentum) Is this collision considered to be elastic or inelastic? conservation of kinetic ener What role did uncertainties play in determining the above two answers? For the above answers that were conserved, were they perfectly conserved? If not, why? What muld have been the outcome if the Velcro was not present? How would the conservation of momentum or kinetic energy have changed? '' JConclusion What is the most surprising thing you learned in the lab today? How are the ideas learned in the lab today relevant to your area of study? How are the ideas learned in the lab today relevant to the world in general? ' Questions Under what conditions should you use conservation of momentum to solve collision problems? Under what conditions should you use conservation of kinetic energy? You are playing football and an opponent with momentum exactly opposite yours runs into you. Would you prefer the opponent small, large, or does it make no difference? Explain. Consider the following situations: a. A ball moving at speed (v) is brought to rest. b. The same ball is projected from rest so that it moves with speed {v}. 12 13 Consider the following situations: a. A ball moving at speed (v) is brought to rest. I b. The same ball is projected from rest so that it | moves with speed (v). I c. The same ball moving at speed (v) is brought to ' rest, then projected backward to its original speed. 14 lln which of the above cases does the ball undergo the largest change in momentum? Explain. 15 Suppose rain falls vertically into an open cart rolling along a straight, horizontal track with negligible friction. As a result of the accumulating water, will the speed of the cart increase, decrease, or stay the same? Explain. 16 1? Is it possible for a stationary object that has been struck by a moving object, to move away with more velocity than the original object was moving with? Explain. 18 16 Suppose rain falls vertically into an open cart rolling along a straight, horizontal track with negligible friction. As a result of the accumulating water, will the speed of the cart increase, decrease, or stay the same? Explain. 17 18 19 Is it possible for a stationary object that has been struck by a moving object, to move away with more velocity than the original object was moving with? Explain. Two masses, m1 and m2, approach each other on a m table and collide. Is it possible that, as a result of the collision, all the kinetic energy of both masses is converted to heat? If so, under what circumstances? Explain. Z1 J7.