Rotational Velocity and Acceleration

In summary, electric toothbrushes with a 1.1 cm diameter head that rotates at an angle of 70.0 degrees 7600 times per minute can effectively remove dental plaque. Assuming constant angular acceleration in each direction, the angular acceleration in rad/sec2 and tangential acceleration in m/s2 can be found.
  • #1
PhysicsScrub
5
0
1. Electric toothbrushes can be effective in removing dental plaque. One model consists of a head 1.1 cm in diameter that rotates back and forth through a 70.0 angle 7600 times per minute. The rim of the head contains a thin row of bristles. (See the figure )Assuming that the toothbrush has constant angular acceleration in each of the directions it turns, find the angular acceleration (in rad/sec2 ) of the rotating head and the tangential acceleration (in m/s2 ) of the bristles.


What is the rotational acceleration in rad/sec2

What is tangental accelration in m/s2
 
Last edited:
Physics news on Phys.org
  • #2
Seriously? A toothbrush 1.1 inches in diameter? Is it for horses?
 
  • #3
gneill said:
Seriously? A toothbrush 1.1 inches in diameter? Is it for horses?

Oops. that should say 1.1 cm
 
  • #4
PhysicsScrub said:
Oops. that should say 1.1 cm

Phew! You had me worried for a moment there :smile:

So assuming that the brush goes from zero to angle seventy degrees in a half period, what is the required angular acceleration?
 
  • #5
gneill said:
Phew! You had me worried for a moment there :smile:

So assuming that the brush goes from zero to angle seventy degrees in a half period, what is the required angular acceleration?

realllly unsure bud
 
  • #6
Well, if it goes back and forth 7600 times every minute, what's the period for one cycle?
 

Related to Rotational Velocity and Acceleration

1. What is rotational velocity?

Rotational velocity, also known as angular velocity, is the measure of how fast an object is rotating around a specific axis. It is usually measured in radians per second or degrees per second.

2. How is rotational velocity different from linear velocity?

Rotational velocity and linear velocity are both measures of an object's speed, but they differ in the direction of motion. Rotational velocity describes the speed of an object as it spins around an axis, while linear velocity describes the speed of an object as it moves in a straight line.

3. What is the relationship between rotational velocity and angular acceleration?

Angular acceleration is the rate of change of rotational velocity. This means that if an object's rotational velocity is increasing or decreasing, it is experiencing angular acceleration. The relationship between the two is similar to that of linear velocity and linear acceleration - the greater the angular acceleration, the faster the object's rotational velocity will change.

4. How is rotational velocity measured?

Rotational velocity can be measured using a variety of tools, such as a tachometer or an accelerometer. A tachometer measures the rotational speed of an object by counting the number of rotations per unit of time. An accelerometer measures the change in rotational velocity over time and can be used to calculate the object's average angular velocity.

5. What factors affect an object's rotational velocity?

Several factors can affect an object's rotational velocity, including the object's mass, shape, and distance from the axis of rotation. The torque applied to the object and the moment of inertia, which is a measure of how resistant an object is to changes in rotational motion, also play a role in determining the object's rotational velocity.

Similar threads

Replies
12
Views
826
Replies
7
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
984
  • Introductory Physics Homework Help
Replies
2
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
3K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
2K
Back
Top