IB MYP Integrated Sciences e-Assessment : Wave phenomena and wave equation Exam Style Practice Questions - New Syllabus
Question (8 marks)
Some students are investigating paper helicopters. They use an electric fan to simulate the wind and measure the horizontal distance the seeds move. The table below shows the seeds used for this investigation:
| Seed A | Seed B | Seed C |
|---|---|---|
| Length of each wing: 3 cm | Length of each wing: 2 cm | Length of each wing: 4 cm |
Question (2 marks)
Use the concept of air resistance to select the seed which you predict will move the greatest horizontal distance when the fan is set on speed 3. Justify your answer.
▶️Answer/Explanation
Seed C:
– Seed C has the longest wings (4 cm), which means it has the largest surface area.
– A larger surface area increases air resistance, allowing the seed to stay airborne longer and travel a greater horizontal distance.
– Therefore, Seed C is predicted to move the greatest horizontal distance when the fan is set on speed 3.
Question (4 marks)
There are several errors in the method seen in the video. Identify two errors in the method and outline how these errors will affect the time recorded.
▶️Answer/Explanation
Error 1: The fan speed was not consistent.
– Effect: Inconsistent fan speed will lead to inconsistent wind conditions, causing variations in the time recorded for the seeds to travel the same distance.
Error 2: The height from which the seeds were dropped was not constant.
– Effect: Dropping the seeds from different heights will result in different initial velocities, affecting the time recorded for the seeds to reach the ground.
Question (1 mark)
Outline how one of the errors from your answer in part (b) could be corrected.
▶️Answer/Explanation
Correction for Error 1:
– Use a fan with a consistent speed setting and ensure that the fan is placed at the same distance from the seeds for each trial.
– This will ensure that the wind conditions are consistent, leading to more accurate and reliable time recordings.
Question (1 mark)
Suggest a different independent variable that could be investigated to extend this investigation.
▶️Answer/Explanation
Independent Variable: The angle at which the seeds are dropped.
– By changing the angle at which the seeds are dropped, the effect of the angle on the horizontal distance traveled can be investigated.
Question (2 marks)
Seeds can be dispersed by the wind. The students decide to adapt the experiment to find out how far the wind disperses different types of seeds. They use an electric fan to simulate the wind and measure the horizontal distance the seeds move.
Use the concept of air resistance to select the seed which you predict will move the greatest horizontal distance when the fan is set on speed 3. Justify your answer.
▶️Answer/Explanation
Seed C:
– Seed C has the longest wings (4 cm), which means it has the largest surface area.
– A larger surface area increases air resistance, allowing the seed to stay airborne longer and travel a greater horizontal distance.
– Therefore, Seed C is predicted to move the greatest horizontal distance when the fan is set on speed 3.
Question (2 marks)
Outline why it might be an advantage for a tree to disperse its seeds over a greater horizontal distance.
▶️Answer/Explanation
Advantage of Seed Dispersal:
– Dispersing seeds over a greater horizontal distance reduces competition for resources (such as light, water, and nutrients) between the parent tree and its offspring.
– It also increases the chances of the seeds landing in a suitable environment for germination and growth, reducing the risk of overcrowding and disease.
– Additionally, it helps the species colonize new areas, increasing genetic diversity and resilience.