วันพุธที่ 18 มกราคม พ.ศ. 2560

In this year.I am new to Panyarat High School so it has a lot of thing change like friends,  teachers and place.I don't do anything very special in this year.I only know new teacher, new friends and new school.I think next year my friends and I have a lot of thing to do more than this year. Good luck








Stratus is long cloud
Cumulus is fluffy white cloud
Cirrus is thin featherlike cloud

วันพุธที่ 4 มกราคม พ.ศ. 2560

The Effect of Gravity on Speed

Introduction
Gravity provides a constant acceleration (force) on an object.  The effect is changed by using ramps at different angles. In this lab, you will find the optimal angle to maximize acceleration on a ball bearing so it travels the farthest and/or the fastest.  Friction is the opposing force created by the surface interactions.  Whenever something rolls due to a force, friction will oppose this force and slow it down.

Equipment needed:
Timer                                       Ramp                           Ball Bearing
Graph Paper (2)                       Ruler                                      

Procedure:
1.         Put the ramp against the seat of a chair.  Place the ramp and chair so that the ramp points towards the hallway.  Have your teammate on the other end of the hallway. 
2.         Place the ball bearing at the top of the ramp.
3.         Lift the ramp 20 cm and release the ball bearing
4.         Time how long it takes to travel  5 meters.
5.         See how far it will go..
6.         Repeat the experiment three times for each height then do 40 cm, 60 cm, and 80 cm.

Height
Time to travel 5 meters
Distance travelled
20
 4.4

20
 4

20
 4.3

40
 5.2

40
 5.3

40
 5.8

60
 7

60
 6.7

60
7.2 











Observations: 20 is fastest because ball not bounce


1.Describe how the ball rolls off the ramp at each height-discuss the effect of bouncing or other factors.

20 - ball not bounce    fastest

40 - ball bounce a bit   slow

60 - ball bounce a lot   slowest

In the speed of the ball will be less and lost control of direction when it hit surface.

2.Discuss what is the fastest speed reached and any factors that could improve this.

4.0 seconds. smoother ramp and slip floor.

3.Does the ball travel in a straight line, why or why not?

No because ball is not flat so ball can move around with round surface in any direction.