Rotation

We can measure only angular sizes and angular distances for objects in the sky because they are very far away from us, making their physical size and distance impractical to measure directly. By measuring their angular sizes and distances, we can calculate properties such as their actual size and distance using geometric principles and known relationships.

The angular diameter of the sun is about 31 to 32 arcminutes, which is roughly the same as the full moon.

Rotation refers to the spinning of an object around its own axis, like the Earth rotating on its axis every 24 hours. Revolution refers to an object moving around another object along a specific path, like the Earth revolving around the Sun in a year. Both rotation and revolution are important astronomical phenomena that govern the movement of celestial bodies in space.

it takes Jupiter approximately 87.969 days to complete one full orbit around the sun, also known as one full revolution.

The Earth spins at a speed of approximately 1,000 miles per hour at the equator. This rotation causes day and night as different parts of the Earth face or move away from the sun during the course of a 24-hour day.

In the northern hemisphere, whirlpools rotate counterclockwise due to the Coriolis effect, which is caused by the Earth's rotation. This effect causes fluids to deflect to the right in the northern hemisphere, leading to counterclockwise rotation in large bodies of water such as whirlpools.

No, because gravity has to do with mass, not rotation.

If it weren't for gravity, the rotation would cause people to fly off into space. Every object is supposed to go in a straight path forever, unless countered by another object. For example:

If you have a a circle, with a small opening (_) (but with the bottom slightly more rounded), and you put a marble inside and gave it a slight push, it would go around the ring, till it reaches the opening, where it will leave in a straight path. The thing stopping it is the ring, exerting an inward force on it. The Earths rotation is pushing us in our natural straight path, and gravity is like the ring, stopping us from leaving by exerting an inward force on us towards the center of the Earth (the surface is keeping us from going to the core; the surface of Earth acts as the ring, also pushing an inward force on us , which to us will push us out. However, gravity keeps us from floating, for being so strong. The gravity is so strong because of the close distance between us and the Earth, plus the Earths mass is very large).

Anyway, rotation causes us to leave Earth in our natural straight path, and Earths gravity keeps us here; henceforth, Gravity and Rotation have nothing to do with each other.

I apologize if there is any mistakes (probably not, but perhaps). I am not a teacher nor an adult, so it is plausible that I have some information wrong, nothing major, but perhaps a few words here and there are incorrect. It should be overall correct.

If the Earth's rate of rotation were to decrease, days would become longer as it would take more time for the Earth to complete one rotation. This change in rotation speed would impact weather patterns, ocean currents, and potentially have a significant effect on Earth's ecosystem and climate.

The tilt of Earth's rotation axis creates the different seasons by causing the amount of sunlight received at a given location to vary throughout the year. This tilt also affects climate patterns and the distribution of temperatures on Earth's surface, impacting weather systems and ecosystems.

You create a purely 'rotatory force' or torque when you have two forces of equal magnitude but opposite direction pushing or pulling on an object. The greater the forces the greater the torque, and the greater the perpendicular distances between the two forces the greater the torque.

Note that because the forces are equal and opposite, the object will not accelerate in any direction. But because there is a perpendicular distance between the forces the object will start to rotate.

Angular unconformities form when previously deposited rock layers are tilted or folded, eroded, and then overlain by younger, horizontal layers. This tilting and erosion create an angular discordance between the older and younger rock layers. This process often signifies a significant gap in the geologic record.

A solid disk will roll faster down an incline compared to a hoop because more mass is concentrated at the center of the disk, which increases its rotational inertia and supports the rolling motion. The distribution of mass in a hoop is more spread out, leading to lower rotational inertia and a slower rolling speed.

Velocity of satellite and hence its linear momentum changes continuously due to the change in the direction of motion in a circular orbit. However, angular momentum is conserved as no external torque acts on the satellite.

Newton's first law states that an object at rest will stay at rest, and an object in motion will stay in motion at a constant velocity unless acted upon by an external force. This means that an object will continue its current state of motion unless another force acts upon it to change that motion. It is often referred to as the law of inertia.

No, angular speed is a scalar quantity. It represents how fast an object is rotating around an axis and is measured in radians per second. It does not have a directional component like a vector quantity.

Let's be very accurate when describing accelerations in this question.

Consider a person at the equator. The gravitational force of attraction on him is constant whether or not the earth is rotating. This acceleration is called the acceleration due to gravity (ag)

Now, since the earth is rotating about its axis, there has to be a centripetal force on the person. It is the gravitational force which provides the centripetal force. Thus, there is a centripetal acceleration on the person (ac)

Finally, the rest of the gravitational force causes the person to accelerate towards earth. This is called the acceleration of free fall (af)

This gives ag = ac + af

ac is given by the equation: ac = w2r

where w is the angular velocity and r is the radius of rotation

If the angular velocity of the earth increases, centripetal acceleration will increase.

af = ag - w2r

Therefore, the acceleration of free fall will decrease.

The local zenith is perpendicular to the rotation axis of the Earth at a specific location. It represents the point directly above an observer, pointing towards the celestial sphere. The rotation axis of the Earth is an imaginary line around which the Earth spins.

Large fan blades have more mass and therefore more inertia, which allows them to keep rotating for a longer time before friction and air resistance slow them down. On the other hand, shorter blades have less mass and less inertia, causing them to stop rotating more quickly.

No, the direction shells spiral in is determined by the genetics of the species. The influence of the Coriolis force on something as small as a sea shell is negligible.

Momentum is a vector quantity, calculated as the product of an object's mass and velocity. Its SI unit is kilogram meters per second (kg m/s), which represents the combination of mass (kg) and velocity (m/s) in defining momentum. Momentum does not have a separate designated unit name because it is derived from fundamental SI units.

yes, a fan is an example of a circular motion

Because we are moving along with the earth, and there is no relative motion between the earth and us. If we are seated on a train and watching the scenery go by, we don't "feel" the motion of the train as it sails down the track at freeway speeds (the jostling of the train aside). Same thing. It's a "frame of reference" thing from physics 101.

Yes, that's correct. The angular diameter of an object decreases as its distance from the observer increases. This relationship is based on the formula for angular diameter, which states that the apparent size of an object in the sky depends on both its actual size and its distance from the observer.

The rotation time of the Earth is approximately 24 hours, which is the time it takes for the Earth to make one complete rotation on its axis. This rotation is what causes day and night on Earth. The rotation speed can vary slightly due to factors like seasonal changes and gravitational interactions with other celestial bodies.

The rotation of the Earth is the Earth spinning on its axis, the pole extending from north to south, once every 23 hours 56 minutes and 4 seconds, roughly.

Revolution is the word describing earth's yearly orbit around the sun.

There are several implications of the Earth's rottation, for example: days and nights, timezones, different length of the daytime during the year (it's because rotation, revolution and axial tilt of the Earth). You can observe Earth's rotation, solar time changing, seasonal Earth's time changing etc. on Earth Time Clock (see: related links)