Net force calculation worksheet with illustrated scenarios for physics students.

Problem: PS Ch 5 Net Force Worksheet

We will solve each problem step by step, calculating the net force and determining whether it is balanced or unbalanced.

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#### 1. Look at the picture to the right. What is the net force on the car?

- Forces acting on the car:
- A force of 7 N to the left.
- A force of 10 N to the right.

- Net force calculation:
- Forces in opposite directions subtract from each other.
- Net force = \( 10 \, \text{N (right)} - 7 \, \text{N (left)} = 3 \, \text{N (right)} \).

- Is the force balanced or unbalanced?
- Since the net force is not zero, the forces are unbalanced.

- Answer:
- Net force = \( \boxed{3 \, \text{N (right)}} \)
- Balanced or unbalanced: Unbalanced

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#### 2. Look at the picture to the left. The dog is pulling with a force of 30 N to the right, and the boy is pulling backwards with a force of 18 N. What is the net force on them?

- Forces acting:
- Dog pulls with 30 N to the right.
- Boy pulls with 18 N to the left.

- Net force calculation:
- Forces in opposite directions subtract from each other.
- Net force = \( 30 \, \text{N (right)} - 18 \, \text{N (left)} = 12 \, \text{N (right)} \).

- Is the force balanced or unbalanced?
- Since the net force is not zero, the forces are unbalanced.

- Answer:
- Net force = \( \boxed{12 \, \text{N (right)}} \)
- Balanced or unbalanced: Unbalanced

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#### 3. Look at the picture to the right. Both men are pushing on the refrigerator with a force of 100 N. What is the net force on the refrigerator?

- Forces acting:
- Both men push with 100 N to the right.

- Net force calculation:
- Forces in the same direction add together.
- Net force = \( 100 \, \text{N (right)} + 100 \, \text{N (right)} = 200 \, \text{N (right)} \).

- Is the force balanced or unbalanced?
- Since the net force is not zero, the forces are unbalanced.

- Answer:
- Net force = \( \boxed{200 \, \text{N (right)}} \)
- Balanced or unbalanced: Unbalanced

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#### 4. Look at the picture to the left. Both of the people on the left are pulling with a force of 30 N to the left. On the right side of the rope, one person is pulling with 35 N to the right, and the other person is pulling with 20 N to the right. What is the net force on the rope?

- Forces acting:
- Left side: Two people pull with 30 N each to the left.
- Total force to the left = \( 30 \, \text{N} + 30 \, \text{N} = 60 \, \text{N (left)} \).
- Right side: Two people pull with 35 N and 20 N to the right.
- Total force to the right = \( 35 \, \text{N} + 20 \, \text{N} = 55 \, \text{N (right)} \).

- Net force calculation:
- Forces in opposite directions subtract from each other.
- Net force = \( 60 \, \text{N (left)} - 55 \, \text{N (right)} = 5 \, \text{N (left)} \).

- Is the force balanced or unbalanced?
- Since the net force is not zero, the forces are unbalanced.

- Answer:
- Net force = \( \boxed{5 \, \text{N (left)}} \)
- Balanced or unbalanced: Unbalanced

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#### 5. Look at the picture to the right. The Jet is traveling with a force of 1000 N. The friction of the air causes a force of about 50 N on the Jet. What is the net force of the Jet?

- Forces acting:
- Engine thrust: 1000 N to the right.
- Air friction: 50 N to the left.

- Net force calculation:
- Forces in opposite directions subtract from each other.
- Net force = \( 1000 \, \text{N (right)} - 50 \, \text{N (left)} = 950 \, \text{N (right)} \).

- Is the force balanced or unbalanced?
- Since the net force is not zero, the forces are unbalanced.

- Answer:
- Net force = \( \boxed{950 \, \text{N (right)}} \)
- Balanced or unbalanced: Unbalanced

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Final Answers:

1. Net force = \( \boxed{3 \, \text{N (right)}} \), Unbalanced
2. Net force = \( \boxed{12 \, \text{N (right)}} \), Unbalanced
3. Net force = \( \boxed{200 \, \text{N (right)}} \), Unbalanced
4. Net force = \( \boxed{5 \, \text{N (left)}} \), Unbalanced
5. Net force = \( \boxed{950 \, \text{N (right)}} \), Unbalanced

Final Boxed Answers:
\[
\boxed{
\begin{array}{ll}
1. & 3 \, \text{N (right)}, \, \text{Unbalanced} \\
2. & 12 \, \text{N (right)}, \, \text{Unbalanced} \\
3. & 200 \, \text{N (right)}, \, \text{Unbalanced} \\
4. & 5 \, \text{N (left)}, \, \text{Unbalanced} \\
5. & 950 \, \text{N (right)}, \, \text{Unbalanced} \\
\end{array}
}
\]