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
A sphere of volume 1.20×10−3m3 hangs from a cable. When the sphere is completely submerged in water, the tension in the cable is
KATRIN_1 [288]

Answer:

B = 62.9 N

Explanation:

This is an exercise on Archimedes' principle, where the thrust force equals the weight of the  liquid

         B = ρ g V

write the equilibrium equation

         T + B -W = 0

         B = W- T               (1)

use the density to write the weight

         ρ = m / V

        m = ρ V

         W = ρ g V

substitute in  1

         B = m g -T

         B = \rho_{body} g V - T

To finish the calculation, the density of the material must be known, suppose it is steel  \rho_{body} = 7850 kg / m³

calculate

         B = 7850 9.8 1.20 10⁻³ - 29.4

          B = 92.3 - 29.4

          B = 62.9 N

4 0
3 years ago
Which image illustrates the bouncing of a light wave off of a surface?
Naily [24]

Answer:

The answer is A good luck :P

8 0
3 years ago
Read 2 more answers
A uniform string of length 0.50 m is fixed at both ends. Find the
kozerog [31]

Answer:

configuration of string:

Node - Antinode - Node    or N-A-N

This is 1/2 wavelength since a full wavelength is N-A-N-A-N

f (fundamental) = V / wavelength

F0 = 300 m/s / 1 m = 100 / sec

F1 = 300 m/s / .5 m = 600 / sec

Each increase is a multiple of the fundamental since the wavelength

increases by 1/2 wavelength to keep nodes at both ends of the string

4 0
3 years ago
The period T of a pendulum of length L is measured to determine g at the surface of Earth. The equation used is T=2π√L/g. The ma
saul85 [17]

Answer:

C: Variation in the value of g as the pendulum bob moves along its arc.

Explanation:

The formula for period of a simple pendulum is given by;

T = 2π√(L/g)

Where;

L is length

g is acceleration due to gravity

Now, from this period equation, it is clear that the only thing that can affect the period of a simple pendulum are changes to its length and acceleration due to gravity.

Looking at the options, the only one that talks about either the length or gravity as being potential causes of the error is option C

4 0
3 years ago
From Kepler's third law, an asteroid with an orbital period of 8 years lies at an average distance from the Sun equal to:
bazaltina [42]

Answer:

The correct option is (B).

Explanation:

The Kepler's third law of motion gives the relationship between the orbital time period and the distance from the semi major axis such that,

T^2\propto a^3\\\\T^2=ka^3

It is mentioned that, an asteroid with an orbital period of 8 years. So,

(8)^2=ka^3\\\\64=ka^3\\\\a=(64)^{\dfrac{1}{3}}\\\\a=4\ AU

So, an asteroid with an orbital period of 8 years lies at an average distance from the Sun equal to 4 astronomical units.

7 0
3 years ago
Other questions:
  • -<br> Speed is a scalar, a quantity that is<br> described by<br> alone.
    8·1 answer
  • he Volume in an experiment is changed (in mL) is 200, 100, 50, 25, 12.5 and we measured the pressure (in atm) is 0.1000, 0.2000,
    15·1 answer
  • A straight trail with a uniform inclination of 15 degrees leads from a lodge at an elevation of 600 feet to a mountain lake at a
    14·1 answer
  • A very fine thread is placed between two glass plates on one side and the other side is touching to form a wedge. A beam of mono
    5·1 answer
  • A body moving at .500c with respect to an observer
    10·1 answer
  • A wire loop of radius 0.37 m lies so that an external magnetic field of magnitude 0.35 T is perpendicular to the loop. The field
    15·1 answer
  • Plz helppppppp I need helpppppp
    9·1 answer
  • The Sun orbits the center of the Galaxy in 225 million years at a distance of 26,000 lightyears. Given that a^3 = (M1 +M2) x P^2
    7·1 answer
  • A vibrating pendulum makes 20 complete vibrations in 12.2 seconds. Determine the vibrational period of the pendulum, along with
    6·1 answer
  • Two 20kg spheres are placed with their
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!