Transcript 5 N
Directions To view this presentation correctly click “Slideshow” then “From Beginning”. Read carefully and take notes. Balanced & Unbalanced Forces Forces Instant Replay Go through the PowerPoint and take detailed notes. Page titles should be sub headings within your notes. Newton’s Law of Motion says: “In order to move an object with mass, you need to apply a force” The greater the mass = The greater inertia => more force is needed Force • What is force? – Push or Pull • It’s what causes “things” to accelerate 1000 kg Balanced vs. Unbalanced Forces • If all forces are balanced there is no acceleration in any direction. – (Either Zero Motion or Constant Velocity) • If one force is greater than the opposing force we get acceleration in a direction. Balanced Forces (Balanced Forces = No Acceleration) 5N Object Notice that all the forces are equally pointed in the opposite direction. Hence they balance each other – or cancel each other. 5N Equal Pushing Forces may cancel each other and produce a Net Force of 0! Balanced Forces Example (Balanced Forces = No Acceleration) Ground pushes up Gravity pulls down Gravity pulls down on you… The ground pushes back up… THIS KEEPS YOU WHERE YOU ARE! If these football players push on each other equally as hard, will either one move? Balanced Forces Example (Balanced Forces = No Acceleration) 5N 5N Equal Pushing Equal Pulling 5N 5N Forces may cancel each other and produce No Acceleration! Unbalanced Forces Cause Acceleration Adding Forces Subtracting Forces Adding Forces 5N 5 N = 10 N • Two forces in the same direction are added together to produce a net force. – Positive Acceleration occurs (Speed up) Unbalanced Forces Causes Acceleration Adding Forces 5N Object 5N Notice that all the forces are pointed in the same direction. Hence they add together. Subtracting Forces 10 N =5N 5N • When forces are in opposite directions you subtract to produce a net force that will move in the direction of the larger force. – Negative Acceleration occurs (Slow Down) Unbalanced Forces Causes Acceleration Subtracting Forces 20 N 5N Object Net Force of 15N to the Right Notice that the forces are unequal and pointed in the opposite direction. Hence they are unbalanced and in opposition to each other – or one partially cancels the other. Balanced Forces 10N 10N 10N Balanced Push i.e. Pushing a Car No Change in Motion 10N Balanced Pull i.e. Tug-o-war No Change in Motion Un-Balanced Forces Additive Un-Balanced Same Direction 10N 10N Moves 20 N to the Right. so you ADD 10 + 10 Subtractive 20N 10N Un-Balanced Opposite Direction So you SUBTRACT 20 - 10 Moves 10 N to the right