What Affects How Parachutes Fall - Essay Example

What Affects How Parachutes Fall? Roll No: Teacher: What affects how parachutes fall? Every phenomenon that wecan observe and inform about nowadays has its scientific explanation and with the help of this explanation, the reasons about the happening of a certain action can be known. Everything that falls towards the earth has some forces that drag it to the earth. Parachutes can be taken as an example of falling objects towards earth. However, parachutes do not fall themselves, they are made to fall (Singh 2009). There are certain forces that affect the falling of a parachute. Parachutes do not fall freely because of presence of certain resistances that hinder the movement of a parachute towards earth (White 1968). A parachute falls towards earth because of two major factors, which are weight (mass) of the parachute and the speed with which it falls towards the earth. Now, the question arises, how weight and speed affect the falling of a parachute towards the ground. Our investigation is based on the hypothesis: “weight of a parachute and its speed affect its falling towards the earth”. Now, there are many factors that contribute towards the weight and speed of a parachute while it is falling, which are gravity and air pressure. Gravity is a factor that attracts everything towards the centre of earth. That is the same factor, which helps us to walk and stick to ground. Everything in air falls towards the ground because of gravity. The force of gravity is such that every free falling body accelerates with an acceleration of 9.8m/s2 (Walsh 1985). At this acceleration, the body takes much lesser time to hit ground. Therefore, when parachute is dropped, it falls towards the ground. We know that: W=mg W= weight, m= mass and g= gravity The weight of a body depends on its mass and gravity, as these are the factors that allot a body with some weight. The weight of a falling parachute is calculated with the help of its gravity and mass (the space, which it occupies). It shows that weight of a parachute affects its falling towards the ground. Now as we know that a falling parachute not shows a free fall as in free fall, acceleration increases by 9.8m/s2, which is a very fast acceleration (Walsh 1985). The body having this acceleration also has a great velocity. If the parachute having this great velocity and acceleration falls, then it will smash itself after hitting ground (White 1968). Instead, in general, parachute never shows a free fall. Then what are the factors that slow the velocity of a parachute down. Air resistance is a factor that maintains the velocity of a parachute. As we know, air is a mixture of gases. These gases are made up of molecules. Anything, which exerts force to these molecules, is opposed by equal amount of force exerted by the molecules, which is a practical description of Newton’s third law that is “For every action there is an equal and opposite reaction” (Corporation 2003). This is the same law that is applied to a ball-hitting wall, which returns with same velocity. The overall effect produces a drag that reduces speed but keeps its motion constant (Walsh 1985). The speed of a parachute can further be reduced by Increasing the surface area of the parachute. Lowering the weight attached to the parachute. By increasing the surface area of the parachute, we can reduce the velocity of parachute (Walsh 1985). Increasing the surface areas will increase the opposition to the air molecules, which will eventually increase the air resistance, and more the air resistance, less will be the speed of parachute. If the weight attached to the parachute is lowered then its velocity can be reduced (Walsh 1985). Lesser the weight attached to the parachute, lower will be the speed of parachute. There are some other effects, which can affect the velocity and drag of a parachute which are as follows. Humidity Shape Wind Humidity is the approximate amount of water molecules present in air which are mixed with air molecules. So if the air contains more water molecules, the air will be denser than that of air which contains lesser water molecules. The Parachute which is dropped in that air which contains higher percentage of water molecules will take more time than that of parachute which is dropped in the air with lesser percentage of water molecules (Corporation 2003). So, higher the percentage of humidity lesser will be the velocity of parachute. The shape of a parachute can also affect its speed. Structural difference in different kinds of parachutes enables them to fall with different speeds and acceleration (Singh 2009). Circular parachutes are the slowest of all because the circular shape of a parachute is able provide the higher air resistance. If a parachute is rectangular in shape it will provide less air resistance so it will move faster than that or circular. Triangular parachutes are the mostly used parachutes and they work well against any kind of resistance (Singh 2009). Their shape accommodates them to fall with much balance and control. Wind affects a parachute by making its fall inclined (Corporation 2003). A parachute which falls to the ground making an inclined path will take higher time to reach the ground instead of the parachute which is making a straight path to the ground (White 1968). So, if the wind has the higher velocity, parachute makes a higher angle of inclination and higher the angle of inclination more time will be required by the parachute to reach the ground. Therefore, it is quite clear that weight and speed are two factors that affect the falling of a parachute towards earth mainly. Humidity, shape and wind are some other factors that are participants of working along with gravity and air pressure to influence the falling of a parachute. The resistive forces in allowing the parachutes to fall freely are accommodating for the parachute users as they make the parachutes to arrive on ground with balance and control. Other forces affect the outcome of a falling parachute are the forces that keep the capacity of reducing and increasing the speed as well as weight of the falling parachutes. References Goldsworthy A, Feasey R (1997), Making Sense of Primary Science Investigations, ASE Publishers. Singh, Manmeet (2009), How does a parachute work?, Retrieved on 9th October 2010 from http://www.buzzle.com/articles/how-does-a-parachute-work.html Walsh, Weston (1985), Parachutes and Terminal Velocity, Retrieved on 9th October 2010 from http://www.sciencebyjones.com/parachutes.htm White, Lynn (1968), "The Invention of the Parachute", Technology and Culture 9 (3): 462–467. Corporation, Marshall Cavendish (2003), How It Works: Science and Technology, Vol. 1, Marshall Cavendish Corporation, US, 1641-1644. Read More