Activity 1: Exploring, Investigating Invisible Forces! Objective: Identify the forces acting on an object at rest and construct a free body diagram of forces acting on an object. What you need: Pictures of a hanging pen and book lying on the table. What to do: Look and study the pictures as shown in Figure 11 and 12. Figure 11. Hanging Pen (Credit: Science 8 LM) Figure 12. A book lying on a table. (http://learnenglishnowinhindi.blogspot.com) เห8 ปีข ระ TI show the table
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