Use your data (attachment) from Part 3 and Newton’s laws to explain why the force meter measures a force if the cart is moving at a constant velocity. You should cover the following points. State Newton’s first law.
• Identify the forces acting on the cart.
• Describe the relationships between applied force and mass and between applied force and weight as linear (from data or mathematical derivation by applying Newton’s first law).
• Explain why the data are linear in terms of Newton’s first law.
• Graph F versus mass + cart.
The cart experiences a frictional force which is directly proportional to its weight. This means that there must be a force applied on the car to balance the forces on the car to produce a net force of 0. This is in accordance to Newton's first law which states that an object at rest will remain at rest and an object in motion will remain in motion unless an external force acts on it. The force must be a resultant force. Therefore, the force needed increases with the total weight of the cart as well as with the added mass in a linear manner.
