Forces Review

Fill in the blanks. Newton's First Law of Motion is also called the Law of Inertia. Newton's First Law says that an object at rest will stay at rest and an object in motion will stay in motion, unless an unbalanced force acts on that object. What property of an object determines how much inertia it will have? weight mass velocity force Which object has more inertia? Bowling ball Tennis ball Which object has more inertia? Hammer Feather Fill in the blanks. Newton's Second Law of Motion says that when a net force is applied to an object, the object will accelerate. The greater the applied force, the greater the acceleration the object will experience. When a smaller force is applied, the object will experience a smaller acceleration. What is the Newton's Second Law formula? F = ma F = m F = a Fill in the blanks. Newton's Third Law of Motion states that forces exist in pairs. This means that for every action force there is also a reaction force. These forces are equal in magnitude, but act in opposite directions. Match each action force with the appropriate reaction force. A bat hitting a baseball. The baseball hitting the bat. Your finger pressing on your phone while texting. Your phone pushing back on your finger. Your body leaning against a wall. The wall pushing back on your body. Sort each of the following scenarios as being examples of Newton's First, Second, or Third Laws. Newton's First Law Your body moving forward and being caught by your seat belt when you slam on the brakes in your car. A softball moving through the air until it is caught by an outfielder's glove. Newton's Second Law A worker exerting a net force of 20 Newtons on a 5 kg crate, causing the crate to accelerate across the floor at a rate of 4 m Newton's Third Law A hammer exerting a force on a nail, and the nail exerting an equal and opposite force back on the hammer. A cannon exerting a force to shoot a cannonball, and the cannonball exerting a force back on the cannon, causing it to kick or roll backward.