Which of the following forces is needed to pick up your school bag?

Options

A. Muscular force
B. Gravitational force
C. Magnetic force
D. Electrostatic force

Explanation

To determine the force needed to pick up your school bag, we can analyze the situation step by step.

### Step-by-Step Solution:

1. **Identify the Object**: The object in question is your school bag.

2. **Understand the Forces Acting on the Bag**: When you pick up the bag, the primary force acting on it is gravity, which pulls it downwards. This force is equal to the weight of the bag.

3. **Determine the Weight of the Bag**: The weight (W) of the bag can be calculated using the formula:
\[ W = m \cdot g \]
where \(m\) is the mass of the bag and \(g\) is the acceleration due to gravity (approximately \(9.8 \, \text{m/s}^2\)).

4. **Calculate the Force Required to Lift the Bag**: To lift the bag, you need to exert an upward force that is equal to or greater than the weight of the bag. Therefore, the force (F) you need to apply is:
\[ F = W \]
This means you need to exert a force equal to the weight of the bag to lift it.

5. **Conclusion**: The force needed to pick up your school bag is equal to the weight of the bag, which is determined by its mass and the acceleration due to gravity.

### Final Answer:
The force needed to pick up your school bag is equal to its weight.

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