laws of motion

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Issac Newton discovered the three laws of motion

• 1st law of motion
• if the net force (the vector sum of all forces acting on an object) is zero, then the velocity of the object is constant
• thought experiment A
• a stationary iceboat is resting on the ice angled at 70 degrees away from true north
• there is no wind
• in this situation there are no forces acting on the boat, thus the boat will remain at rest with a constant velocity of zero
• thought experiment B
• an iceboat is sailing angled at 70 degrees away from true north
• wind is blowing at 12 mph from the true north
• skipper has sheeted to a certain tension on the boom and placed the sheet line in the jam cleat
• eventually on the 70 degree course the iceboat reaches steady state and is neither speeding up or slowing down
• the boat is not hiking or side slipping on its runners
• both experiments A and B are examples of the 1st law of motion
• 2nd law of motion
• force = mass * acceleration
• 3rd law of motion