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
butalik [34]
3 years ago
14

When a carpenter shuts off his circular saw, the 10.0 inch diameter blade slows from 4250 rpm to 0.00 in 4.00 s. (a) What is the

angular acceleration of the blade? (b) What is the distance traveled by a point on the rim of the blade during the deceleration? (c) What is the magnitude of the displacement of a point on the rim of the blade during the deceleration?
Physics
1 answer:
MaRussiya [10]3 years ago
4 0

Answer:

(a) \alpha=-111.26rad/s

(b) s=4450.6in

(c) 8.66in

Explanation:

First change the units of the velocity, using these equivalents 1rev=2\pi rad and 1 min =60s

4250rpm(\frac{2\pi rad}{1rev})(\frac{1 min}{60 s} )=445.06rad/s

The angular acceleration \alpha the time rate of change of the angular speed \omega according to:

\alpha=\frac{\Delta \omega}{\Delta t}

\Delta  \omega=\omega_i-\omega_f

Where \omega_i is the original velocity, in the case the velocity before starting the deceleration, and \omega_f is the final velocity, equal to zero because it has stopped.

\alpha=\frac{\Delta \omega}{\Delta t} =\frac{\omega_i-\omega_f}{4}\frac{0-445.06}{4} =\frac{-445.06}{4} =-111.26rad/s

b) To find the distance traveled in radians use the formula:

\theta = \omega_i t + \frac{1}{2} \alpha t^2

\theta = 445.06 (4) + \frac{1}{2}(-111.26) (4)^2=1780.24-890.12=890.12rad

To change this result to inches, solve the angular displacement \theta for the distance traveled s (r is the radius).

\theta=\frac{s}{r} \\s=\theta r

s=890.12(5)=4450.6in

c) The displacement is the difference between the original position and the final. But in every complete rotation of the rim, the point returns to its original position. so is needed to know how many rotations did the point in the 890.16 rad of distant traveled:

\frac{890.12}{2\pi}=141.6667

The real difference is in the 0.6667 (or 2/3) of the rotation. To find the distance  between these positions imagine a triangle formed with the center of the blade (point C), the initial position (point A) and the final position (point B). The angle \gamma=\frac{2\pi}{3}=\frac{360^o}{3}=120 is between the two sides known. Using the theorem of the cosine we can find the missing side of the the triangle(which  is also the net displacement):

c^2=a^2+b^2-2abcos(\gamma)

c^2=5^2+5^2-2(5)(5)cos(\frac{2\pi}{3} )\\c^2=25+25+25\\c^2=75\\c=5\sqrt{3}=8.66in

You might be interested in
You are at the top of the Empire State Building on the 102nd floor, which is located 373 m above the ground, when your favorite
Liula [17]

Answer:

1.5 m

Explanation:

H = actual height of the superhero = ?

H₀ = height of the superhero as observed = 1.73 m

v = speed of the superhero = 0.50 c

Using the equation

H = H_{o} \sqrt{1 - \left ( \frac{v}{c} \right )^{2}}

Inserting the values

H = 1.73 \sqrt{1 - \left ( \frac{0.50 c}{c} \right )^{2}}

H = 1.5 m

3 0
3 years ago
Ideally, rewards should be given immediately and frequently but
snow_lady [41]
The correct answer for the question that is being presented above is this one: "a. only from an instructor or supervisor." Ideally, rewards should be given immediately and frequently but <span>only from an instructor or supervisor to show authority. </span>
3 0
2 years ago
Calculate the minimum thickness (in nm) of an oil slick on water that appears blue when illuminated by white light perpendicular
mr_godi [17]

Answer:

The minimum thickness = 83.92 nm

Explanation:

The relation between the wavelength in a particular medium and refractive index \lambda_n = \frac{ \lambda }{n}

where ;

\lambda = wavelength of the light in vacuum

n = refractive index of medium with respect to vacuum

For one phase change :

2t = \frac{\lambda_n}{2}\\\\where \ \lambda_n = \frac{\lambda}{n}\\\\Then \ \\\\2t = \frac{\lambda}{2n}\\\\t = \frac{\lambda_n}{4n}

Replacing 1.43 for n and 480 nm for λ; we have:

t = \frac{480}{4(1.43)}

t = 83.92 nm

Thus; the minimum thickness = 83.92 nm

4 0
3 years ago
In a motor, the combined effect of electric currents and magnetic forces turn electrical energy into which of the following?
lord [1]
A motor is built to use all those things and produce mechanical energy.
6 0
2 years ago
Read 2 more answers
True or false Weight is constant every place in the universe.
ycow [4]
False. it's depend on g -constant.

6 0
3 years ago
Other questions:
  • What is the wavelength of an earthquake wave if it has a speed of 12 km/s and a frequency of 15 Hz
    7·1 answer
  • If a ball is rolling across a floor at a constant speed is it accelerating
    10·1 answer
  • What is the relationship between height and gravitational potential energy of water behind a dam?
    13·1 answer
  • What do most scientists think causes Bovine Spongiform Encephalopathy (Mad Cow Disease)?
    6·2 answers
  • Under many conditions, the center of mass of a system of particles can represent the system as a whole. But how far does this ru
    14·2 answers
  • Instructions:Select the correct answer from the drop-down menu. The Longmenshan Fault is in China. This fault was created when t
    8·1 answer
  • The location of a particle is measured with an uncertainty of 0.15 nm. One tries to simultaneously measure the velocity of this
    13·1 answer
  • When you are using a crowbar to lift a large rock, you are working agents the force called
    7·1 answer
  • Need help in the middle one
    12·1 answer
  • A diffraction-limited laser of length L and aperture diameter 0.50 cm generates light of wavelength 700nm . If the beam is direc
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!