Unit 5!
Today, we reviewed Newton's three laws of motion, applied them to problems, and went over the different types of forces again. Newton's first law stated that objects in motion or at rest will tend to stay in motion or at rest unless acted upon and outside unbalanced force. Newton's second law said that Force = Mass x Acceleration and Newton's third law said that to every action, there's an equal and opposite reaction. The four forces we learned about were weight force, normal force, tension force, and friction force. Weight force is the force on Earth, also known as gravity, normal force is force that is directly in contact with the object, tension force is force applied on a string, and friction force is force that opposes motion or impending motion.
We also learned how to draw free body diagrams, which was a way to show forces on an object. For me, drawing free body diagrams help me to understand what kind of forces are applied on an object and its affect. For example, in the picture above, there are two different forces affecting the phone. Weight force from gravity pulls it down while normal force from the table pushes it up. Because these forces are the same in magnitude, the object doesn't move. However, if I pushed the phone to the right, I am not only the unbalanced outside force, but I am also the normal force. Because the table has friction, the friction force pushes against the normal force. But my force is stronger than the friction, so I am able to move the phone. If the table's friction was even compared to mine, the phone would stay in place.
No comments:
Post a Comment