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
STALIN [3.7K]
3 years ago
9

A skater makes one revolution per second, f = w/(2p) = 1, with her arms and leg stretched (left). By lowering her leg and bringi

ng her arms close to her chest (right) she reduces her moment of inertia from I to I′ = 0.4I. How many revolutions per second, f′ = w¢/(2p), is she making now? Show all your work.
Physics
2 answers:
mihalych1998 [28]3 years ago
8 0

Answer:

f'=w'/2p=2.49rev/s

Explanation:

The angular momentum L must be equal for both cases.

Hence you have that

L before = L after

L=I\omega

\omega=2\pi f

I = moment of inertia

w =angular momentum

Hence

L=L'\\I\omega =I'\omega'\\\omega'=\frac{I\omega}{I'}=\frac{I*2\pi *1}{0.4I}=15.70\frac{rad}{s}

f'=w'/2p=2.49rev/s

hope this helps!!

Firlakuza [10]3 years ago
4 0

Answer:

Answer is given in the attachment.

Explanation:

Download pdf
You might be interested in
What burns quicker, white or colored candles?
VashaNatasha [74]
White is a hotter color so it burns faster. :)
3 0
3 years ago
When air cools, it holds _____ water than when it is warmer.
Blizzard [7]
It holds A. Less water than when it is warmer.
6 0
3 years ago
Read 2 more answers
Calculate the de Broglie wavelength of (a) a mass of 1.0 g traveling at 1.0 m s−1 , (b) the same, traveling at 1.00 × 105 km s−1
lesantik [10]

Answer:

a)\lambda=6.63\times10^{-31}m

b)\lambda=6.63\times10^{-39}m

c)\lambda=9.97\times10^{-11}m

d)\lambda=4.03\times10^{-36}m

e)λ=∞

Explanation:

De Broglie discovered that an electron or other mass particles can have a wavelength associated, and that wavelength (λ) is:

\lambda=\frac{h}{P}=\frac{h}{mv}

with h the Plank's constant (6.63\times10^{-34}\frac{m^{2}kg}{s}) and P the momentum of the object that is mass (m) times velocity (v).

a)\lambda=\frac{6.63\times10^{-34}}{(1.0\times10^{-3}kg*1.0)}

\lambda=6.63\times10^{-31}m

b)\lambda=\frac{6.63\times10^{-34}}{(1.0\times10^{-3}*(1.00\times10^{8}))}

\lambda=6.63\times10^{-39}m

c)\lambda=\frac{6.63\times10^{-34}}{(6.65\times10^{-27}*1000)}

\lambda=9.97\times10^{-11}m

d)\lambda=\frac{6.63\times10^{-34}}{(74*2.22)}

\lambda=4.03\times10^{-36}m

e) \lambda=\frac{6.63\times10^{-34}}{(74*0)}

λ=∞

6 0
3 years ago
A 35 kg chair is lifted 5M off the ground. what is the potential energy?
patriot [66]

Answer:

mass × gravity ×height. so....that.. Ep = mgh. Ep= 35×9.8×5. Ep = 1715.

Explanation:

8 0
2 years ago
Katelyn (55 kg) is practicing a drop jump in the biomechanics lab. She steps off a plyometrics box, lands on the force plate, an
suter [353]

Answer:

J = 357.5 kg*m/s

Explanation:

  • The impulse exerted on Katelyn when she was on the force plate, is equal to the change in her momentum, according to Newton's 2nd Law.
  • Assuming as the positive direction the upward direction (coincident with the positive y-axis) we can express the initial momentum as follows:

       p_{o} = m*v_{o} = 55 kg * (-3.0 m/s)  (1)

  • By the same token, the final momentum is as follows:

       p_{f} = m*v_{f} = 55 kg * (3.5 m/s)  (2)

  • As we have already said, the impulse J is just equal to the change in momentum, i.e., the difference between (2) and (1):

      J = p_{f} - p_{o} = m* (v_{f} -v_{o}) = 55 kg* (3.5m/s- (-3.0m/s)) = 357.5 kg*m/s (3)

5 0
3 years ago
Other questions:
  • _____ is the frictional force needed to slow an object in motion
    11·2 answers
  • A uniform crate with a mass of 22 kg must be moved up along the 15° incline without tipping. The force P is horizontal. Determin
    8·1 answer
  • Which of the following is an explanation of how the natural world works, based on experimentation?
    13·2 answers
  • Three objects of uniform density—a solid sphere, a solid cylinder, and a hollow cylinder— are placed at the top of an incline (f
    12·1 answer
  • What precautions should be taken on board a vessel during a lightning storm?
    6·2 answers
  • A gas expands from an initial volume of 30.0 L to a final volume of 65.0 L at a constant pressure of 110kPa. How much work is do
    12·1 answer
  • Light with a wavelength of 600 nm shines onto a single slit, and the diffraction pattern is observed on a screen 2.5 m away from
    9·1 answer
  • State archimedes principle​
    8·1 answer
  • A stunt car traveling at 20 m/s flies horizontally off a cliff and lands 39.2 m from the base of the cliff. How tall is the clif
    5·1 answer
  • Simple question (Serious answers)
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!