________ curve is a curve traced by the free end of a thread unwound from a circle or a polygon in such a way that the thread is always tight and tangential to the circle or side of the polygon.
The question describes a specific type of curve that is created by unwinding a thread from a base shape, such as a circle or a polygon. The key conditions are that the thread remains tight and is always tangent to the base shape as it is unwound.
Based on the description provided, the curve traced by the free end of the thread is known as an involute. An involute of a curve (the base curve) is the locus of a point on a thread as the thread is unwound from the base curve, keeping the thread taut. When the base curve is a circle, the involute is called the involute of a circle. When the base curve is a polygon, it's typically formed by unwinding the thread along each side successively.
Let's consider why the other options do not fit this definition.
A logarithmic curve is represented by equations involving the logarithm function, typically of the form \(y = a \ln(x)\) or similar variations. These curves describe relationships where one variable changes according to the logarithm of another. They do not represent the path of an unwound thread.
A sinusoidal curve describes periodic oscillations, like sine waves (\(y = A \sin(Bx + C)\) or cosine waves (\(y = A \cos(Bx + C)\)). These curves are fundamental in describing wave phenomena but are unrelated to unwinding a thread from a shape.
An exponential curve is represented by equations involving an exponent, such as \(y = a^x\) or \(y = ae^{bx}\). These curves describe growth or decay processes where the rate of change is proportional to the current value. Like logarithmic and sinusoidal curves, they do not match the geometric description of an unwound thread.
The curve that is specifically defined by the process of unwinding a tight, tangential thread from a base curve (like a circle or polygon) is the involute curve. Therefore, based on the question's description, the correct answer is An involute.
| Curve Type | Description | Fit to Question's Definition? |
|---|---|---|
| Involute | Curve traced by the free end of a tight thread unwound from a base curve (circle, polygon). Thread is always tangential. | Yes |
| Logarithmic | Curve representing logarithmic relationships, typically \(y = a \ln(x)\). | No |
| Sinusoidal | Curve representing periodic oscillations (e.g., sine wave). | No |
| Exponential | Curve representing exponential growth/decay, typically \(y = a^x\). | No |
Involute curves are not just theoretical concepts; they have important practical applications, especially in engineering. One of the most common uses is in the design of gear teeth profiles. Using the involute shape for gear teeth ensures smooth power transmission and reduces wear. The involute profile allows the contact point between meshing teeth to travel along a straight line, which is beneficial for gear operation.
"Pathfinder", an American Spacecraft, landed on the planet _______ in 1997.
_______ is the distance from the pitch circle to the bottom of the tooth space in a gear.
In a Class 3 lever, the effort and load move:
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Directions: Each item in this section consists of a sentence with an underlined word followed by four words (a), (b), (c), and (d). Select the option that is opposite in meaning to the underlined word and mark your response in your Answer Sheet accordingly.
The major source of vitamins and minerals for vegetarians is
Which of the following statements about the Deccan Riots Commission is/are correct?
1. The Commission did not hold enquiries in the districts which were not affected.
2. The Commission did record the statements of ryots, sahukars and eye-witnesses.
Select the correct answer using the code given below: