Question

conclusion: 5) what is resisting the net force (σf) of the counterweight pulling on the cart: the cart’s inertia or weight? 6) explain your answer! (hint: what direction does gravity pull and what direction is the string pulling the cart?) 7) what happened to the acceleration of the cart when the mass of the cart remained unchanged but the net force (σf) being applied to the cart by the counterweight increased? 8) explain your answer! use the word ratio in your answer.

Explanation:

Step1: Analyze force - resistance concept

Inertia resists changes in motion. Weight is a force due to gravity.

Step2: Consider force directions

Gravity acts vertically downwards. The string pulling the cart is horizontal (assuming a typical setup). The cart's inertia resists the change in its motion caused by the net - force of the counterweight.

Step3: Apply Newton's second law for question 7

Newton's second law is $F = ma$, where $F$ is the net - force, $m$ is the mass, and $a$ is the acceleration. If $m$ is constant and $F$ increases, then $a$ increases.

Step4: Explain using ratio for question 8

From $F = ma$, we can write the ratio $\frac{F}{m}=a$. When $m$ is fixed and $F$ increases, the ratio $\frac{F}{m}$ increases, so the acceleration $a$ increases.

Answer:

1. The cart's inertia.
2. Gravity acts vertically downwards and the string pulling the cart is usually in a horizontal direction. Inertia resists changes in the cart's motion, while weight acts perpendicular to the direction of the pull from the counter - weight.
3. The acceleration of the cart increases.
4. According to Newton's second law $F = ma$, or $\frac{F}{m}=a$. When the mass $m$ of the cart is unchanged and the net - force $F$ increases, the ratio of the net - force to the mass increases, so the acceleration of the cart increases.