5. No external force The body remains at rest. The body moves with a constant speed . Newton’s first Law
6.
7. For fixed force A body with a larger mass moves with a smaller acceleration . A body with a smaller mass moves with a larger acceleration . Newton’s second Law
8. For fixed mass A body with a smaller net force moves with a smaller acceleration . A body with a larger net force moves with a larger acceleration . Newton’s second Law
9.
10. Body A exerts a force on body B, then body B exerts an equal and opposite force on body A. Newton’s third Law Body A Body B Force on B by A Force on A by B
13. Circular Motion in horizontal circles Angular velocity = / t Linear velocity v = r Centripetal force F = m r 2 = m v 2 / r Centripetal acceleration a = r 2 = v 2 / r
15. Circular Motion in horizontal circles Conical pendulum Do you remember what kind of forces provides the centripetal force to the bob ? Tension T Weight mg Centripetal force
16. Vertical circular motion Bucket and water Does the water spill out the bucket when whirling ? If no, why doesn’t it spill out ?
17. Vertical circular motion Bucket and water What kind of motion does the bucket perform ? Vertical circular motion What kind of force provides the centripetal force F c to the bucket ? Tension T Weight mg
18. Vertical circular motion Bucket and water What kind of force provides the centripetal force F c to the bucket at the highest position ? F c = T + mg Tension T Weight mg
19. Vertical circular motion Bucket and water What kind of force provides the centripetal force F c to the bucket at the lowest position ? F c = T - mg Tension T Weight mg
20. Vertical circular motion Bucket and water What kind of force provides the centripetal force F c to the water at the highest position ? F c = R + W Reaction of the bucket R Weight of water W
21. Vertical circular motion Bucket and water What kind of force provides the centripetal force F c to the bucket at the lowest position ? F c = R - W Reaction of the bucket R Weight of water W
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