Directions: Use the information provided and your knowledge of Physical Science to answer the following questions. Show all work where necessary.
Directions: Use the information provided and your knowledge of Physical Science to answer the following questions. Show all work where necessary.
Diagram 1.
Source:
https://wallpaperaccess.com/tug-of-war
In a tug-of-war using a rolling cart/platform, when two groups pull in opposite directions, the cart moves toward the side with the greater total pull. If both sides pull equally, the cart does not speed up.
Forces are pushes or pulls. Often, more than one force acts on an object at the same time. To predict how an object’s motion will change, we need to consider the net force, which is the sum of all the forces acting on the object. When forces act in opposite directions, the net force is found by subtracting the smaller force from the larger one. The direction of the net force is the direction of the stronger side.
In this tug-of-war investigation, a cart is pulled left and right at the same time. If the pulls are equal, the forces are balanced and the net force is
If one side pulls harder than the other, the forces are unbalanced. The net force is not zero, and the cart’s motion changes. A nonzero net force causes the cart to accelerate in the direction of the net force, meaning its speed increases in that direction.
Newton’s Second Law explains how force and mass work together: acceleration depends on the net force and the mass of the object. For the same cart (constant mass), a larger net force causes a larger acceleration. That means a cart pulled with a net force of
By measuring the pull forces on both sides, calculating net force, and measuring acceleration, students can collect evidence that the change in motion depends on the sum of the forces and the mass of the object.
Table 1.
Trial | Left Force (N) | Right Force (N) | Net Force (N) | Mass (kg) | Acceleration (m/s2) |
|---|---|---|---|---|---|
1 | 5 | 5 | 0 | 2 | 0 |
2 | 6 | 7 | 1 | 2 | 0.5 |
3 | 7 | 9 | 2 | 2 | 1 |
4 | 8 | 8 | 0 | 2 | 0 |
5 | 9 | 10 | 1 | 2 | 0.5 |
Graph of Information - Figure 1.
Table 2.
Net Force (N) | Acceleration (m/s2) | Direction | Change From Zero (m/s2) |
|---|---|---|---|
0 | 0 | None | 0 |
1 | 0.5 | Right | 0.5 |
2 | 1 | Right | 1 |
Graph of Information - Figure 2.
Using the reading, explain what happens to the cart’s motion when the left and right pull forces are equal.
Using Table 1, describe how the cart’s acceleration changes when the net force increases from 0 N to 2 N while mass stays constant.
Which observation best supports the claim that a nonzero net force causes a change in motion?
How does the tug-of-war setup show that forces act on more than one object during the interaction?
Which conclusion is best supported by Figure 1?
Do you agree or disagree with the statement: “In tug-of-war, the cart moves toward the side that pulls harder because the net force points that way, and a larger net force causes a larger change in motion”? Use evidence from the investigation to support your answer.
Claim:
Evidence:
Reasoning: