What theory held that the earth was the center of the universe and that the sun, moon, and planets revolved around it?

About how long does it take ocean water to travel around a gyre?

mylen [45]

The Gulf Stream, for example, has an average speed of 4 mph, or 100 miles/day, or 3600 miles/year, in round numbers. A complete circuit around the Atlantic is 8 or 10 thousand miles, which would take around 3 years on a raft.

4 0

3 years ago

Four examples of compounds which are classed as carbohydrate

Solnce55 [7]

Answer:

Carbohydrates are divided into four types: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Monosaccharides consist of a simple sugar; that is, they have the chemical formula C 6 H 12 O 6. Disaccharides are two simple sugars. Oligosaccharides are three to six monosaccharide units, and polysaccharides are more than six.

6 0

3 years ago

All isotopes of a particular element have the same atomic number. How then do the isotopes of a particular element differ?

xz_007 [3.2K]

Isotopes of an element will contain the same number of protons and electrons but will differ in the number of neutrons they contain. In other words, isotopes have the same atomic number because they are the same element but have a different atomic mass because they contain a different number of neutrons

7 0

3 years ago

When the play button is pressed, a CD accelerates uniformly from rest to 450 rev/min in 3.0 revolutions. If the CD has a radius

Marina CMI [18]

To solve this problem it is necessary to apply the kinematic equations of angular motion.

Torque from the rotational movement is defined as

$\tau = I\alpha$

where

I = Moment of inertia $\rightarrow \frac{1}{2}mr^2$ For a disk

$\alpha =$ Angular acceleration

The angular acceleration at the same time can be defined as function of angular velocity and angular displacement (Without considering time) through the expression:

$2 \alpha \theta = \omega_f^2-\omega_i^2$

Where

$\omega_{f,i} =$ Final and Initial Angular velocity

$\alpha =$ Angular acceleration

$\theta =$ Angular displacement

Our values are given as

$\omega_i = 0 rad/s$

$\omega_f = 450rev/min (\frac{1min}{60s})(\frac{2\pi rad}{1rev})$

$\omega_f = 47.12rad/s$

$\theta = 3 rev (\frac{2\pi rad}{1rev}) \rightarrow 6\pi rad$

$r = 7cm = 7*10^{-2}m$

$m = 17g = 17*10^{-3}kg$

Using the expression of angular acceleration we can find the to then find the torque, that is,

$2\alpha\theta=\omega_f^2-\omega_i^2$

$\alpha=\frac{\omega_f^2-\omega_i^2}{2\theta}$

$\alpha = \frac{47.12^2-0^2}{2*6\pi}$

$\alpha = 58.89rad/s^2$

With the expression of the acceleration found it is now necessary to replace it on the torque equation and the respective moment of inertia for the disk, so

$\tau = I\alpha$

$\tau = (\frac{1}{2}mr^2)\alpha$