An oscillating pendulum stops, because its energy

Options

A. Changes into kinetic energy
B. Change into potential energy
C. Change into heat energy
D. Is destroyed

Answer

To solve the question regarding why an oscillating pendulum stops, we need to analyze the energy transformations involved in its motion. Here’s a step-by-step breakdown:

### Step 1: Understanding Pendulum Motion
A pendulum consists of a mass (the bob) attached to a string that swings back and forth under the influence of gravity. When the pendulum is in motion, it has both kinetic energy (due to its speed) and potential energy (due to its height).

**Hint:** Remember that a pendulum's energy alternates between kinetic and potential as it swings.

### Step 2: Energy Transformation
As the pendulum swings, it converts potential energy to kinetic energy and vice versa. At the highest points of its swing, the pendulum has maximum potential energy and minimum kinetic energy. At the lowest point, it has maximum kinetic energy and minimum potential energy.

**Hint:** Identify the points in the swing where potential and kinetic energy are at their maximum and minimum.

### Step 3: Damping Forces
Over time, the pendulum will slow down and eventually stop. This is primarily due to damping forces such as air resistance. Air resistance acts against the motion of the pendulum, converting some of its mechanical energy into other forms of energy.

**Hint:** Consider what happens to the energy when a force opposes the motion of an object.

### Step 4: Energy Conversion to Heat
The energy lost due to air resistance is transformed into heat energy. This means that the mechanical energy of the pendulum (the sum of its kinetic and potential energy) is not conserved; instead, it is dissipated as heat.

**Hint:** Think about how energy can be transformed into different forms, especially when friction or drag is involved.

### Step 5: Conclusion
The oscillating pendulum stops because its mechanical energy is converted into heat energy due to air resistance. Therefore, the correct answer to the question is that the energy changes into heat energy.

**Final Answer:** The oscillating pendulum stops because its energy changes into heat energy.

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