清英：2b u6 Hickory Dickory Dock<br><div>手工：make a sundial </div> make a sundial<div>Scientists build equipment to help them exam the world around them.The oldest clock ever built is probably the sundial and they're great fun to make.</div><div><br></div><div>1.Poke a pencil through the middle of a paper plate. Place it upside down outside. At 7 oclock in the morning make a dot where the shadow of the Pencil falls and write the number 7.<br>If sunrise is after 7 o'clock, start the project later.</div><div><br></div><div>2.At 8 o'clock. mark the shadow again and write an 8. Keep doing this once an hour until sunset, marking the shadow and writing the hour next to it .<br>Once finished, you can use the shadow of the pencil to tell the time Just be careful not to move the plate</div><div><br></div><div>Why does the shadow move?<br>Shadows cast by the Sun are always on the opposite side from the Sun This means that as the Sun moves across the sky, the pencil shadow oves around the opposite side of the plate It's the same movement every day, so once you've marked le times, you can use the sundial as a clock. The only time it wont work is when it's cloudy!</div><div><br><div><br></div></div> <div>【发明简史6】时间专题：子疯教你做日晷<br></div>https://www.bilibili.com/video/BV1ef4y197vK?from=search&seid=9802075810040741983