# What is the speed of the disk?

• ChaNgeD
In summary, the disk is rotating at 3 revolutions per second and the force exerted by the wire is 0.050kg. The speed of the disk is 95km/h. The coefficient of friction between the object and the road must be .050kg for the car to round a 85m radius curve. The orbital speed of the satellite is 1.01384x10^-4m/s.

#### ChaNgeD

I have not attempted to work on these, the only attempt I've done was look and stare at the questions and not know where to start or even begin the problem. I do not know which formula to use either. given is highlighted in bold lettering. Unfortunately i have other homework and these problems are due tommorow so urgent help is needed thx!

3. .050kg disk attached to the end of a .150-m wire revovles uniformly on a flat, frictionless surface.

a) moving 3 revolutions per second, what is the force exerted by the wire on the object?

b)What is the speed of the disk?

4.How large must the coefficent of friction be between the tires and the road if the car is to round a level curve of radius 85m at a speed if 95 km/h?

6. A satilite is place in orbit 6.00x10^6. Jupiter has a mass of 1.90x10^7 and radius of 7.5x10^7. Find the orbital speed.

7. The outer radius of saturns rings are 170,000. Find the period of the outer radius.

You need to show at least some effort before we can help you! I find it hard to believe that you have no equations in your textbook or class notes that will help you on these problems.

The hardest problem for me is deciding which formula to use and if i ussualy find the formula i can plug the numbers in the problem and solve it. Here is what i have probably isn't right lols if it is OMG for me !lols
3. Still have no clue on the formula for this one.

4. v^2 = 95^2
----- ------ = 106.18
r 85
6. GMm
------
r^2
(6.67x10^-11)(6.00x10^6)(1.90x10^7)
-------------------------------------- = 1.01384x10^-4
(7.5x10^7)
7. F = m v^2 / r
I have no clue if this is the right formula and what to plugin lols..

6. A satilite is place in orbit 6.00x10^6. Jupiter has a mass of 1.90x10^7 and radius of 7.5x10^7. Find the orbital speed.

...6 x 10^6 Whats? Meters? Lemons?

Your problems all sound like applications of Newton's Laws of motion. Here is a basic strategy:
1. Draw a picture, draw the system(object) of interest large and show any interaction(s) with the environment.
2. Draw the forces acting on your system. Might want to choose a coordinate system to work in now.
3. Apply Newton's second in each direction. Stare at the picture to determine what you might be able to say about the acceleration in any direction.
4. Solve. This depends on the problem. You should remember formulae like that for the circumference of a circle or what the frictional force depends on, etc. Having these memorized will help you think about getting to the solution through a series of steps, hopefully.
Good luck.

## 1. What is the speed of the disk?

The speed of a disk refers to how fast it rotates or spins. It is typically measured in revolutions per minute (RPM) or rotations per minute.

## 2. How is the speed of a disk measured?

The speed of a disk can be measured using a tachometer, which is a device that measures the number of rotations per minute. It can also be calculated by measuring the time it takes for one full rotation and using the equation RPM = 1/Time.

## 3. Does the speed of a disk affect its performance?

Yes, the speed of a disk can greatly impact its performance. A higher speed allows for faster data transfer and access times, making the disk more efficient. However, other factors such as the type of disk and its interface also play a role in overall performance.

## 4. What is the difference between rotational speed and transfer speed?

Rotational speed refers to how fast the disk is spinning, while transfer speed refers to how quickly data can be read from or written to the disk. A disk with a higher rotational speed will generally have a faster transfer speed, but this can also be affected by other factors such as the disk's interface and data density.

## 5. Can the speed of a disk be increased?

Yes, the speed of a disk can be increased by upgrading to a higher RPM disk or by using a solid-state drive (SSD) which has no moving parts and can access data much faster than traditional spinning disks. However, the maximum speed of a disk is limited by its physical components and interface, so it is important to choose a disk with the appropriate speed for your needs.