# Investigating Terminal Velocity Essay example

835 Words 4 Pages
Investigating Terminal Velocity

Introduction

When an object falls through a fluid it accelerates until it reaches its terminal velocity. At this speed the forces acting on it are balanced.

My task is to investigate the factors that affect the terminal velocity of a falling object.

Key Factors

· Mass of ball bearing
· Viscosity/density of the fluid
· Surface area of ball bearing
· Texture of the balls surface
· Temperature

I am going to investigate how mass affects the terminal velocity.

Prediction

I think that as the mass of the ball bearing increases so does the weight of the ball bearing, which requires more friction to balance the ball bearing's weight thus making the terminal velocity increase.
The elastic bands were placed on the tube so that there are markers for the timing to be started and stopped on a fixed point.
A group of ball bearings were massed with an electric balance and an average of the ball bearings were taken. These ball bearings were massed so that an average mass could be calculated for each size of the ball bearings, by dividing the total mass of the ball bearings by the number of ball bearings.
The ball bearing was placed on the fluids surface and let to fall through the fluid.
A stop clock was started when the ball bearing reached the first elastic band and stopped when it reached the second elastic band.
The results were repeated three times for an accurate average time and any "strange results" were repeated to improve accuracy.
The results are shown in a table on the next page.

Diagram

Results

Average mass results

Ball Number of Balls Mass (g) (2dp) Average mass of one ball (g) (2dp)
A 60 1.80 0.03
B 30 3.37 0.11
C 50 22.07 0.44
D 50 44.20 0.88
E 30 61.54 2.05

Terminal Velocity Results

Average mass (g) (2dp) Distance Fallen (cm) (1dp) Time of Fall (s) (1dp) Terminal Velocity (cm/s) (1dp) Trial 1 Trial 2 Trial 3 Average
0.03 60.0 50.4 48.6 48.9 49.3 1.2
0.11 60.0 22.9 20.6 20.8 21.4 2.8
0.44 60.0 10.3 10.2 10.3 10.3 5.8
0.88 60.0 7.1 7.0 6.5 6.9 8.7
2.05 60