1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Oksanka [162]
2 years ago
10

A bug is 12 cm from the center of a turntable that is rotating with a frequency of 45 rev/min . What minimum coefficient frictio

n is required so that the bug stays on the turntable?
Physics
1 answer:
Agata [3.3K]2 years ago
3 0

Answer:

The minimum coefficient of friction is 0.27.

Explanation:

To solve this problem, start with identifying the forces at play here. First, the bug staying on the rotating turntable will be subject to the centripetal force constantly acting toward the center of the turntable (in absence of which the bug would leave the turntable in a straight line). Second, there is the force of friction due to which the bug can stick to the table. The friction force acts as an intermediary to enable the centripetal acceleration to happen.

Centripetal force is written as

F_c = m\frac{v^2}{r}

with v the linear velocity and r the radius of the turntable. We are not given v, but we can write it as

v = r\omega

with ω denoting the angular velocity, which we are given. With that, the above becomes:

F_c = m\frac{v^2}{r}=m\omega^2 r

Now, the friction force must be at least as much (in magnitude) as Fc. The coefficient (static) of friction μ must be large enough. How large?

F_r=\mu mg \geq m\omega^2 r = F_c\implies\\\mu \geq \frac{\omega^2 r}{g}

Let's plug in the numbers. The angular velocity should be in radians per second. We are given rev/min, which can be easily transformed by a factor 2pi/60:

\frac{1 rev}{1 min}\cdot\frac{\frac{2\pi rad}{rev}}{\frac{60s}{1 min}}=\frac{2\pi}{60}\frac{rad}{s}

and so 45 rev/min = 4.71 rad/s.

\mu \geq \frac{\omega^2 r}{g}=\frac{4.71^2\frac{1}{s^2}\cdot 0.12m}{9.8\frac{m}{s^2}}=0.27

A static coefficient of friction of at least be 0.27 must be present for the bug to continue enjoying the ride on the turntable.



You might be interested in
Your cousin is moving into an apartment in San Francisco. This apartment is on a street that is angled at 25∘ above the horizont
Vesnalui [34]

Answer:

70

Explanation:

5 0
3 years ago
A semicircular plate with radius 6 m is submerged vertically in water so that the top is 2 m above the surface. Express the hydr
dalvyx [7]

Answer: 313920

Explanation:First, we’re going to assume that the top of the circular plate surface is 2 meters under the water. Next, we will set up the axis system so that the origin of the axis system is at the center of the plate.

Finally, we will again split up the plate into n horizontal strips each of width Δy and we’ll choose a point y∗ from each strip. Attached to this is a sketch of the set up.

The water’s surface is shown at the top of the sketch. Below the water’s surface is the circular plate and a standard xy-axis system is superimposed on the circle with the center of the circle at the origin of the axis system. It is shown that the distance from the water’s surface and the top of the plate is 6 meters and the distance from the water’s surface to the x-axis (and hence the center of the plate) is 8 meters.

The depth below the water surface of each strip is,

di = 8 − yi

and that in turn gives us the pressure on the strip,

Pi =ρgdi = 9810 (8−yi)

The area of each strip is,

Ai = 2√4− (yi) 2Δy

The hydrostatic force on each strip is,

Fi = Pi Ai=9810 (8−yi) (2) √4−(yi)² Δy

The total force on the plate is found on the attached image.

5 0
3 years ago
As water across the surface of the earth it dissolves material as it travels. What property of water does this demonstrate?
iris [78.8K]

Answer:

B) Water is a solvent

Explanation:

Among many other chemicals, water can dissolve a variety of substances. The solvent properties of chemicals are far beyond it. That property makes water a universal solvent.

Water has one atom of oxygen and two atoms of hydrogen.

One side of the water molecule is positively charged and the other side is negatively charged. This property attracts other substances like salt and disintegrates into positive and negatively charged ions. This property is due to its physical and chemical nature.

3 0
3 years ago
Which type of electromagnetic wave has the greatest wavelength?
s344n2d4d5 [400]
Radio waves are the longest
5 0
3 years ago
The 480 g bar is rotating as shown what is the angular momentum of the bar about the axle?
Greeley [361]
On a similar problem wherein instead of 480 g, a 650 gram of bar is used:

Angular momentum L = Iω, where 
<span>I = the moment of inertia about the axis of rotation, which for a long thin uniform rod rotating about its center as depicted in the diagram would be 1/12mℓ², where m is the mass of the rod and ℓ is its length. The mass of this particular rod is not given but the length of 2 meters is. The moment of inertia is therefore </span>
<span>I = 1/12m*2² = 1/3m kg*m² </span>

<span>The angular momentum ω = 2πf, where f is the frequency of rotation. If the angular momentum is to be in SI units, this frequency must be in revolutions per second. 120 rpm is 2 rev/s, so </span>
<span>ω = 2π * 2 rev/s = 4π s^(-1) </span>

<span>The angular momentum would therefore be </span>
<span>L = Iω </span>
<span>= 1/3m * 4π </span>
<span>= 4/3πm kg*m²/s, where m is the rod's mass in kg. </span>

<span>The direction of the angular momentum vector - pseudovector, actually - would be straight out of the diagram toward the viewer. </span>

<span>Edit: 650 g = 0.650 kg, so </span>
<span>L = 4/3π(0.650) kg*m²/s </span>
<span>≈ 2.72 kg*m²/s</span>
4 0
2 years ago
Other questions:
  • Plz help don’t understand
    12·1 answer
  • A ball is thrown vertically upward with a speed of 12.0 m/s. (<br> a. How high does it rise?
    10·1 answer
  • A satellite orbiting above the earth needs no power source to keep orbiting the earth. The best explanation for this involves th
    11·2 answers
  • What is the resistance of a 1.3-m-long copper wire that is 0.30 mm in diameter?
    9·1 answer
  • An ornament of mass 42.0 g is attached to a vertical ideal spring with a force constant (spring constant) of 33.9 N/m. The ornam
    7·1 answer
  • A 20g book laying on a 40cm high table. Just before a cat knocks it off the table what is the books gravitational potential ener
    9·1 answer
  • Suppose a car is traveling at 18.6 m/s, and the driver sees a traffic light turn red. After 0.500 s has elapsed (the reaction ti
    6·1 answer
  • How much time would it take a train locomotive running at 6000 Horsepower to use the
    9·1 answer
  • HELP I WILL GIVE BRAINLYEST!!
    12·1 answer
  • a 30-cm-tall, 6.0-cm-diameter cylindrical beaker is filled to its brim with water. part a what is the downward force of the wate
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!