Which of these is an example of muscular force?

Options

A. A magnet sticking to the door of a fridge
B. A boy picking up a dried leaf from the ground
C. A ball rolling on the ground, stopping after a while
D. A flower falling off a tree, always heading towards the ground

Answer

To determine which of the given examples is an example of muscular force, let's analyze each option step by step.

### Step 1: Understand the Definition of Muscular Force
Muscular force is the force exerted by muscles when they contract. It is responsible for moving objects or applying pressure through physical effort.

### Step 2: Analyze Each Example
1. **Magnet sticking to the door of a fridge**:
- This is an example of magnetic force, not muscular force. The magnet's attraction to the metal door is due to magnetic properties, not muscle action.

2. **Boy picking up the dried leaves from the ground**:
- In this case, the boy is using his muscles to lift the leaves. The force exerted by the boy's muscles to pick up the leaves is indeed an example of muscular force.

3. **A ball rolling on the ground stops after a while**:
- The ball stops due to friction and inertia, not muscular force. This example does not involve any muscle exertion.

4. **The flower falling off a tree always heading toward the ground**:
- This is an example of gravitational force. The flower falls due to the pull of gravity, not because of any muscular action.

### Step 3: Conclusion
After analyzing all the examples, the only scenario that involves muscular force is the second option: **Boy picking up the dried leaves from the ground**.

### Final Answer
The example of muscular force is: **Boy picking up the dried leaves from the ground**.

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