Air Flow & Ink Bottle

Objective:

To demonstrate that a duct increases air flow 

Outcome:

Students will understand that a duct supports airflow and enhances the air flow.

Requirements:

2 similar sized bottles with plastic caps(ink bottle size) containing a coloured liquid, 2 plastic basins with water, stopwatch

Prerequisites:

 A conceptual knowledge of 

1. flow of air
2. Ducting
3. Both air and water act similar as fluid mediums 

Procedure:

Step 1: Make a small hole in the plastic cap of the small coloured bottle.

Step 2: Start the stopwatch. Immerse the bottle into the basin with water. Observe the water changing color as the ink flows out into the water. 

Step 3: Allow the entire coloured ink to flow out into the water. Record the time when the bottle is empty.

Step 4: Take the other coloured bottle and make a small hole to fit a straw.

Step 5: Reduce the size of the straw by cutting in the middle and insert the straw into the cap of the bottle.

Step 6: Immerse the bottle with the straw into the basin with clear water. Observe the water changing colour as the ink flows out into the water through the straw.

Step 7: Record the time taken for emptying the ink bottle.

Step 8: Compare the two time recordings and reason out why the bottle with straw took lesser time as compared to the bottle without straw.

References:

None