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
topjm [15]
3 years ago
12

A wheel initially spinning at wo = 50.0 rad/s comes to a halt in 20.0 seconds. Determine the constant angular acceleration and t

he number of revolutions it makes before stopping. An athlete is holding a 2.5 meter pole by one end. The pole makes an angle of 60 with the horizontal. The mass of the pole is 4 kg. Determine the torque exerted by the pole on the athlete's hand. (The mass of the pole can be assumed to be concentrated at the center of mass.)
Physics
1 answer:
svetlana [45]3 years ago
8 0

Answer:

(I). The angular acceleration and number of revolution are -2.5 rad/s² and 500 rad.

(II). The torque is 84.87 N-m.

Explanation:

Given that,

Initial spinning = 50.0 rad/s

Time = 20.0

Distance = 2.5 m

Mass of pole = 4 kg

Angle = 60°

We need to calculate the angular acceleration

Using formula of angular velocity

\omega=-\alpha t

\alpha=-\dfrac{\omega}{t}

\alpha=-\dfrac{50.0}{20.0}

\alpha=-2.5\ rad/s^2

The angular acceleration is -2.5 rad/s²

We need to calculate the number of revolution

Using angular equation of motion

\theta=\omega_{0}t+\dfrac{1}{2}\alpha t

Put the value into the formula

\theta=50\times20-\dfrac{1}{2}\times2.5\times20^2

\theta=500\ rad

The number of revolution is 500 rad.

(II). We need to calculate the torque

Using formula of torque

\vec{\tau}=\vec{r}\times\vec{f}

\tau=r\times f\sin\theta

Put the value into the formula

\tau=2.5\times4\times 9.8\sin60

\tau=84.87\ N-m

Hence, (I). The angular acceleration and number of revolution are -2.5 rad/s² and 500 rad.

(II). The torque is 84.87 N-m.

You might be interested in
An unknown gas fills a cubical container of 0.87 m. If the mass of the gas is 0.316 g, what is the density of the gas ?
svetlana [45]

Answer:

The length of the Mercury column of thermometer at ice point is 20mm and 220mm at steam point . when the same Thermometer is placed in contact with another body ,it reads 5°c.what will the length of the Mercury column at the temperature?

3 0
2 years ago
When magma cools quickly, what kind of texture or
Ksivusya [100]

Answer:

a

Explanation:

when magma cools Crystal's form because the solution is super saturated with respect to some minerals if the magma cools quickly the crystals do not have much time to form hence they are small and also the resulting rock is fine grained

6 0
3 years ago
What is the value of acceleration due to gravity, g, on Earth?
qwelly [4]

Explanation:

It varies with altitude, but at sea level, it's 9.8 m/s².

8 0
3 years ago
What is the wavelength of an earthquake wave if it has a speed of 3 km/s and a frequency of 6 Hz?
disa [49]
Wavelength = c/f.
Wavelength =0.5km
8 0
2 years ago
Which of Newton's motion laws BEST explains WHY a rock falls when it is dropped from a bridge?
erma4kov [3.2K]
It’s A because it stays in motion whenever you drop it
4 0
3 years ago
Read 2 more answers
Other questions:
  • F(x)= 10x-5<br>What is the value of f-1(-4) ?​
    10·2 answers
  • Earth is the _______ planet from the sun.
    14·2 answers
  • A hot-air balloon and its basket are accelerating upward at 0.265 m/s2, propelled by a net upward force of 688 N. A rope of negl
    13·1 answer
  • What kind of destructive force or forces will most likely change the way Stone Mountain looks over the next million years? A) vo
    7·2 answers
  • PLEASEEE HELP ASAP!!!!!
    15·1 answer
  • I need help :(((((((((((
    12·1 answer
  • 100 POINTS + BRAINLIEST, HEART, &amp; FIVE STAR.
    8·1 answer
  • In orbit how high is the altitude
    12·1 answer
  • A merry-go-round at a playground is a circular platform that is mounted parallel to the ground and can rotate about an axis that
    10·1 answer
  • A bullet with a mass of 0.04-kg is traveling horizontally at 1400 m/s when it strikes a stationary target that is balanced on th
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!