1. Introduction

1. Introduction

1.1 Background Research

Most people do not understand the importance of manual gear systems in cars. The ability to drive a car with a manual transmission has long been considered a vital skill, especially for young drivers(Weinberger and CNN, 2012). Decades after Waterhouse's extemporaneous introduction to stick shifts, alterations in the makeup of the automobile and American consumer habits mean learning the manual may not be a practical necessity(Weinberger and CNN, 2012). Many people also have the misconception that cars bigger wheels are faster than cars with smaller wheels, with the same amount of power applied to each wheel. However, it may not be true.

Gears help increase or decrease the torque of a car(Townsend, 2011). If the speed is reduced by the gear ratio, the torque is increased by the same gear ratio (Nord, 2015). If the first gear has a ratio of 3:1, it increases the engine's torque output by three when moving it onto the final drive (How A Car Works, 2017). The car requires high torque when climbing hills and when starting, although they are performed at low speeds(Ravinder and Banothu, 2015). On the other hand, when running at high speeds on level roads, high torque is not needed because of momentum, and it would be better to have just the wheels turning at high speeds(Ravinder and Banothu, 2015). This brings us back to the experiment whereby we used different motors with different gear ratios to measure the torque of each motor.

Wheels are becoming larger and wider, and not just on sports cars—regular ones, too (de Paula, 2011).  The torque is dependent on the magnitude of the force, the point where the force is applied about the axis of rotation and the direction of the force (Cutnell, Johnson, and Fisher, 2009).  According to Newton’s second law, it follows that F=ma (Cutnell, et. Al. , 2009). Newton, (2007) claims that plus sizing may significantly reduce the acceleration, braking and fuel economy of the vehicle. There is a test conducted by Car and Driver to prove this point. Five wheel-and-tire combinations —ranging from 38.1 cm to 48.3 cm— were tested on a 2010 Volkswagen Golf (QUIROGA, 2010). As the wheel-and-tire packages become larger and heavier, acceleration and fuel economy drops(QUIROGA, 2010). A 10-percent reduction in fuel economy and a four-percent degradation in 0 km/h - to - 96.6 km/h acceleration is measured from the 38.1 cm to the 48.3 cm (QUIROGA, 2010). These explanations support the claim raised by de Paula in his article and support our hypothesis whereby as distance increases, the force exerted on the scale decreases.

Thus, if our experiment is a success, we can improve the design of cars, which allow cars to perform to their best ability.
1.2 Research Question
The aim is to determine the relationship between torque and distance and which type of motor produce more torque.

(b) Independent variable
-Distance of the wooden wedge to the centre of the motor shaft, d/cm

-The type of motor
(c) Dependent variable
-The magnitude of the force
(d) Controlled variables
-Amount of voltage used for each motor
-The wedge on the scale must be at the same position throughout
-The wooden wedge and ruler pieces must be tared by the kitchen scale every time for each motor as its reading will affect the magnitude of the force (reading in mass X 9.8 m/s2).
-Kitchen scale must be set at 0 all the time.
-All motors need to stall before disconnecting power.
-Highest reading must be taken for each motor.

1.3 Hypothesis
-The longer the distance from the ruler piece to the centre of the motor shaft, less force needed to stall
the motor and vice versa.

- Motors with higher gear ratio will have higher torque.

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