Investigating the Size of Craters in Sand when a Marble is Dropped into the Sand from Different Heights

When marble falls from different heights into sand, check the size of the crater in the sand. Next, I put a sand bucket on the wall, then leaned against the beach wall by a ruler. * Then I threw the marble into the sand from various heights. * After each autumn, I took a 15 cm ruler, measured the diameter of each crater, and smoothed the surface of the sand.

My chart has some unusual results. This may be because I did not carefully measure the size of the crater or did not pay enough attention when descending marble from different heights. Furthermore, even if you use a fixed frame, you can not see the edge of the crater clearly, so you do not know whether the ruler is completely straight. If you want to repeat this experiment, repeat 5 times so that the ruler is perfectly vertical to the vertical object such as a wall. The sand we use is not fine grain, so we need to sift, but it is still not smooth enough. Next time, we will use very fine sand grains. Because marble has a better surface landing, this will make the crater more obvious, the whole experiment is more reliable

I predict that crater size will increase as marble height decreases. Both marbles are the same. The reason for the increase is due to the increase in kinetic energy as indicated by PE = mgh. Likewise, as the height increases, the kinetic energy and the impact energy also increase because the potential energy increases. Marble has the potential of gravity, and when it is higher, it gains more energy, so there is more power in the sand to make the crater larger. Therefore, I predict that the chart will look like this. -

Assumption: As the height of the falling ball increases, the depth of the crater increases. There is a theory. Higher drop means more gravity potential. When the ball falls, all of this energy is converted to kinetic energy and used to form craters on the ground. Variable: Independent: The height of the pendulum falling from a 1-meter ruler is used to measure the height at which the pendulum falls off the surface of the sand. We record each height and make it a table together with the result