Yesterday, we did a experimen. It was about pendulum. It was fun. First we made a pendulum. We took a piece of string and a ring-shaped rubber. We tied the rubber onto a string. Then we marked length of 10cm 20cm 30cm

40cm and 50cm on the string. We stuck the pendulum on the desk with the tape. We started the experiment. First we changed the length of the string. The timer was set for 30s. One person pulled the rubber. One person started the timer. Other people counted how many times. then we know as the string gets longer it will swing fewer time.

Then we changed the size of swing. My prediction was: as the the swing gets bigger it will swing fewer time. But after the experimen I know they are the same nuber. It was amazing. What a fun experimen!