Newton's Three Laws of Motion Lab Activity
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The mathematical expression of Newton's Second Law of Motion is shown at the right. The Greek symbol on the left is capital sigma. It means "the sum of." F with an arrow over it stands for external force. So, the lefthand side of the equation means "the sum of the external forces acting on an object." The righthand side of the equation stands for "mass times acceleration." Note: The acceleration of an object will always have the same direction as the net force acting on the object.

Watch the video below to learn what Newton's Second Law of Motion means.
Complete the Newton's Second Law of Motion SelfQuiz below. Do not attempt to complete the lab quiz before mastering the problems in the selfquiz!
Newton's Second Law of Motion SelfQuiz
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 A child pulls her baby brother in a wagon. The mass of the baby brother and the wagon together is 45 kilograms. While the child is pulling the wagon, it has an acceleration of 0.85 m/s/s. What is the magnitude of the force exerted by the child on the wagon assuming no other forces are acting on the wagon? Round your answer to two decimal places, and make sure you include the proper SI unit(s).
 A car with a mass of 1650 kilograms is accelerating at 4.0 m/s/s. What is the magnitude of the force causing the car to accelerate? Make sure you use the proper SI unit(s).
 A force of 59 Newtons is exerted on a 68 kilogram woman. What is the magnitude of her acceleration assuming no other forces act on her? Round your answer to two decimal places, and make sure you include the proper SI unit(s).
 An object is pulled across a frictionless surface. When the magnitude of the net force acting on the object is equal to 47 Newtons, it has an acceleration of 0.08 meters/second/second. What is the mass of the object? Round your answer to two decimal places, and make sure you use the proper SI unit(s).
 Three guys each push with 425 Newtons of force on a stalled car. What is the mass of the car if it has an acceleration of 0.85 m/s/s assuming no other forces act on the car? Make sure you include the proper SI unit(s).
 A tennis ball has a mass of 0.314 kilograms and has an acceleration of 164 meters/second/second when it is hit by a racket. What is the magnitude of the net force exerted on the ball assuming no forces other than that by the racket are acting on the ball? Round your answer to two decimal places, and make sure you include the proper SI unit(s).