Seven solar panels were installed in an open field. Each panel was installed at a different fixed tilt angle. The energy output of the seven panels was then measured over a period of exactly one year (366 days).

The results can be found in the table below:

\begin{tabular}{|c|c|c|}
\hline
Panel Number & \begin{tabular}{c}
Tilt (angle with the \\ horizontal plane)
\end{tabular} & Total Annual Energy Output \\
(kWh/year) \\
\hline
1 & [tex]$0^{\circ}$[/tex] & 350 \\
2 & [tex]$10^{\circ}$[/tex] & 370 \\
3 & [tex]$20^{\circ}$[/tex] & 390 \\
4 & [tex]$30^{\circ}$[/tex] & \\
5 & [tex]$40^{\circ}$[/tex] & \\
6 & [tex]$50^{\circ}$[/tex] & \\
7 & [tex]$90^{\circ}$[/tex] & \\
\hline
\end{tabular}

Draw a bar graph to illustrate the annual energy output at different tilt angles for the seven solar panels.



Answer :

To draw a bar graph illustrating the annual energy output at different tilt angles for the seven solar panels, we can follow these steps:

1. Prepare the Data: Collect the given data and note the tilt angles and corresponding energy output values.

Here is the given data:
| Panel Number | Tilt Angle (degrees) | Annual Energy Output (kWh/year) |
|--------------|-----------------------|---------------------------------|
| 1 | 0 | 350 |
| 2 | 10 | 370 |
| 3 | 20 | 390 |
| 4 | 30 | |
| 5 | 40 | |
| 6 | 50 | |
| 7 | 90 | |

2. Choose a Suitable Scale: Decide on an appropriate scale for both the x-axis (tilt angles) and y-axis (energy output).

3. Label the Axes: The x-axis will represent the tilt angle, and the y-axis will represent the annual energy output in kWh/year.

4. Plot the Bars: For each tilt angle, draw a vertical bar corresponding to its annual energy output. For panels with missing data, you can leave the bars empty or use a different color or pattern to indicate that the data is not available.

5. Title the Graph: Provide a title for the graph that accurately describes what the graph is showing.

Here is how to do it:

### Bar Graph Drawing Steps

1. Prepare the Canvas: On a graph paper or graphing tool, draw a set of axes. The horizontal axis (x-axis) will represent tilt angles, labeled from 0 to 90 degrees. The vertical axis (y-axis) will represent the energy output in kWh/year, labeled appropriately based on the data (e.g., from 0 to 400).

2. Plot the Data Points:
- Draw a bar for the panel with a 0-degree tilt at a height of 350.
- Draw a bar for the panel with a 10-degree tilt at a height of 370.
- Draw a bar for the panel with a 20-degree tilt at a height of 390.
- Leave the bars for 30, 40, 50, and 90 degrees as empty or indicate missing data.

3. Add Labels:
- X-Axis Label: "Tilt Angle (degrees)"
- Y-Axis Label: "Annual Energy Output (kWh/year)"
- Title: "Annual Energy Output by Tilt Angle for Seven Solar Panels"

Here is a textual representation of what the bar graph might look like:

```
^ Title: Annual Energy Output by Tilt Angle for Seven Solar Panels
|
| +----------------------------------------------------------+
| Energy Output | |
| (kWh/year) | |
400| | |
| |
|
350| | |
| | |
300| | |
| | |
250| | |
| | |
200| | |
| | |
150| | |
| | |
100| | |
| | |
50| | |
| | |
0| |
+----------------------|----|----|----|----|----|----| | |-------------------|
0 10 20 30 40 50 90
Tilt Angle (degrees)
```

In this representation:
- The '*' symbolize the bars; the height of these bars corresponds to the energy output values.
- Empty spaces for 30, 40, 50, and 90 degrees indicate missing data.

By following these steps, you will be able to create a bar graph that visualizes the annual energy output for solar panels at different tilt angles.