Procedure :
(1) Take a long plastic tube of length nearly 200cm and cut it in half along the length of the tube.
(2) Use these tube parts as tracks.
(3) Mark the readings in cm along the track.
(4) Place the one end of the tube on the book or books and the other end on the floor as shown in the figure.
(5) Keep a steel plate on the floor at the bottom of the track.
(6) Consider the reading at the bottom of the track to be zero.
(7) Take a marble having enough size to travel in the track freely.
(8) Now release marble freely from a certain distance say 40 cm.
(9) Start the digital clock when the marble is released.
(10) It moves down on the track and strikes the steel plate. Stop the digital clock when a sound is produced.
(11) Repeat the same experiment for the same distance 2 and 3 times and note the values of times and calculate the average time ‘t’.
| Distance S (cm) |
Time (t) sec |
Average time |
Acceleration |
|
t1t2 t3 |
t = t1 +t2 +t3/3 |
a =2s/t2 |
(12) Repeat the same experiment for various distances.
(13) Find the average time and acceleration for every trail.
(14) Do the same experiment for various slopes of the track and find accelerations in each case.
(15) Do the same experiment with a small iron block. Find acceleration and draw the S-t graph.
(16) From the equation S = ut + 1/2 at2 (here a = g).
17) We observed that ‘g’ is constant.
