| A | B |
|---|
| Find the acceleration of a 6 kg object when a force of 12 N is applied? | The acceleration is 2 m/s/s |
| Does an elephant or a mouse fall faster in friction-free space? | They fall at the same rate! |
| What is the net force on a 25 kg object accelerating at 2 m/s/s? | The net force is 50 Newtons |
| A 10 newton force pulls to the left. A 10 newton force pulls to the right. What is the object's acceleration? | The acceleration is zero. |
| When an object's acceleration is zero, | the forces on the object are balanced. |
| When the forces on an object are balanced, | the object is moving at a constant velocity. |
| What is the force on a 5 kg object accelerates at 7 meters per second per second? | The net force is 35 newtons. |
| What is the acceleration of a 5 kg freely falling object? | The acceleration is about 10 m/s/s. |
| What is the net force on an object at terminal velocity? | The net force is zero. |
| What is the air friction on a 6.5 kg object that is falling at terminal velocity? | The force is 65 Newtons. |
| Terminal velocity | When air resistance and the froce due to gravity are balanced. |
| free fall | The motion of a falling body when only force acting on it is the force due to gravity. |
| Balanced forces | The sum of all forces is zero. |
| Unbalanced forces | The sum of all forces is not zero. |
| Acceleration when forces are balance | No acceleration when forces are balancedl |
| Acceleration when forces are unbalanced | acceleration will be the net force divided by the mass. |
| S.I. unit for force | newton |
| S.I. unit for mass | kilogram |
| S.I. unit for acceleration | meter / second / second |
| Newton's first law | The law of inertia |
| Newton's second law | F = m a |
| Newton's third law | Action-Reaction Law |
| When two objects interact, the forces will be | Equal in magnitude and opposite in direction. |
| An object will remain at rest unless | an unbalance force accelerates it. |
| An object moving at constant velocity will ________ unless an unbalanced force accelerates it. | continue in a straight line at a constant speed |
| Constant velocity | same speed; straight line |
| constant position | at rest |
| Two cars have a head on collision. | The magnitude of the forces on them will be the same. |
| A moving car hits a parked car with a force of 560 newtons. | The parked car exerts a force of 560 newtons on the moving car. |
| A 3 kg ball hits a 10 kg ball. Which accelerates more? | The 30 newton ball. |
| A 50 newton child collides with a 900 kg parked car. | The force on the car and the child are the opposite directions. |
