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It helps to think as the sine and cosine as coordinates of a unit circle - a circle of radius 1, with center at the origin of the coordinates, i.e., point (0, 0). In this case, as you go around on the circle (starting at the right, coordinates (1, 0), and going counterclockwise), the cosine of the angle is simply the x-coordinate, and the sine of the angle is simply the y-coordinate. At 90°, the x-coordinate is 0, therefore the cosine is 0. Also, at 90° the y-coordinate is 1, therefore the sine is 1 (that's the maximum value it can have).

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Q: Why is it cosine 90 degrees is 0?
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Related questions

What is the cosine of 90 degrees?

The cosine of 90 degrees is zero.

What is the cosine of -90?

Cosine of -90 is 0.

What is the graphic representation of cosine function?

Just like the sine function displaced by pi/2. In other words the cosine equals 1 at 0 degrees, 0 at 90 degrees, -1 at 180 and so on.

What is cos 90?

Cosine of 90 degrees is zero.

Why Ten90' is infinity?

First, I assume the question refers to tan(90 degrees) not Ten90' because (apart from the incorrect spelling of tan) 90' represents 90 minutes or 90/60 degrees = 1.5 degrees. The tangent of an angle is defined as the ratio of sine to cosine of the angle. When that angle is 90 degrees, the cosine is zero and so calculation of tan involves division by 0. And, in mathematics division by 0 is not infinity - it is not defined. So, tan(90) is NOT infinity. It is not defined. tan90 has a positive asymptote when you approach 90 degrees from below but has a negative asymptote when you approach from above.

What should be the angle between force and displacement to get the minimum work and maximum work?

To minimize work, the angle between force and displacement should be 90 degrees (perpendicular). This is because work done is calculated as the dot product of force and displacement vectors, and the cosine of 90 degrees is 0, resulting in zero work. To maximize work, the angle should be 0 degrees (parallel), as the cosine of 0 degrees is 1, resulting in maximum work done.

Why is the cosine of 90 equal to 0?

That is the definition. If you take your unit circle (a circle with radius 1 centered at the origin (0,0). you start at (1,0) and go counterclockwise around the circle 90° you end up at (0,1) that 0 is the cosine of the angle 90° In fact, you don't even need the unit circle. Take a circle of any radius r, and draw a ray at 90 degrees. This will intersect the y-axis. So as above, the coordinates are (0,r) (instead of (0,1)) so cos(90 degrees)=x/r=0/r=0

What is cosine of 0?

In both radians and degrees cos(0) = 1.

Why is it tangent 90 degrees is undefined?

Because it tends to infinity. Additionally, tangent can be expressed as sin theta divided by cos theta. The sine of 90 is 1. The cosine of 90 is 0. That would be 1 divided by 0, or division by zero; which is undefined.

How is cos 90 equal to 0?

The Unit Circle is a circle that has a radius of 1 and a center at the origin. If you look at the unit circle 90 degrees is at the point (0,1). Cosine is equal to the x value of a point on the Unit Circle. The line created to the point (0,1) on the unit circle when the degree is 90 is completely vertical, which in turn makes the x value 0 and thus, cosine of 90 = 0. Read more >> Options >>

What is the inverse of the cosine function?

The inverse of the cosine function is arcosine. The domain is −1 ≤ x ≤ 1 since the range of the cosine function is from -1 to 1. The range is from 0 to pi radians or 0 to 180 degrees.

What is cosine 0?

Cosine 0 is 1