Free Fall
Sample Formal Laboratory Report for Physics on the Picket Fence Lab (CP) without the parachute
Purpose: The purpose of this experiment is to verify the acceleration due to gravity using the picket fence with a photogate, LabPro and LoggerPro software by measuring it with a precision of 0.5% or better.
Theory: All objects, regardless of mass, fall with the same acceleration due to gravity assuming that there is no air resistance. Objects thrown upward or downward and those released from rest are falling freely once they are released. Any freely falling object experiences acceleration directed downward, regardless of the direction of its motion at any instant. The symbol “g” is used for this special acceleration at the Earth’s surface. The value of g is approximately 9.8 m/sec2. Since we are neglecting air friction and assuming that the free fall acceleration is constant, the motion of a freely falling object is equivalent to motion in one dimension under constant acceleration. Therefore the constant acceleration equations can be applied. Objects falling downward only under the influence of gravity can be graphically analyzed with a displacement versus time graph shown by a parabolic curve described in graph 1. This graph shows that as the object is falling, the displacement it travels each second is greater than the prior second. This graph can be mathematically illustrated by the equation
which is the equation for displacement as a function of time.
(y v
t t graph 1 graph 2
Graph 2 shows the velocity as a function of time which is a linear relation for constant acceleration shown by the equation [pic]. Keeping acceleration constant, the graph of acceleration versus time would be a horizontal line at the value of acceleration.
Definition of symbols used: t = time vi = initial velocity a = acceleration
(y = vertical displacement vf = final velocity g = acceleration due to gravity
Method:
1. Set up
Purpose: The purpose of this experiment is to verify the acceleration due to gravity using the picket fence with a photogate, LabPro and LoggerPro software by measuring it with a precision of 0.5% or better.
Theory: All objects, regardless of mass, fall with the same acceleration due to gravity assuming that there is no air resistance. Objects thrown upward or downward and those released from rest are falling freely once they are released. Any freely falling object experiences acceleration directed downward, regardless of the direction of its motion at any instant. The symbol “g” is used for this special acceleration at the Earth’s surface. The value of g is approximately 9.8 m/sec2. Since we are neglecting air friction and assuming that the free fall acceleration is constant, the motion of a freely falling object is equivalent to motion in one dimension under constant acceleration. Therefore the constant acceleration equations can be applied. Objects falling downward only under the influence of gravity can be graphically analyzed with a displacement versus time graph shown by a parabolic curve described in graph 1. This graph shows that as the object is falling, the displacement it travels each second is greater than the prior second. This graph can be mathematically illustrated by the equation
which is the equation for displacement as a function of time.
(y v
t t graph 1 graph 2
Graph 2 shows the velocity as a function of time which is a linear relation for constant acceleration shown by the equation [pic]. Keeping acceleration constant, the graph of acceleration versus time would be a horizontal line at the value of acceleration.
Definition of symbols used: t = time vi = initial velocity a = acceleration
(y = vertical displacement vf = final velocity g = acceleration due to gravity
Method:
1. Set up