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
blondinia [14]
3 years ago
14

You stand on a frictional platform that is rotating at 1.1 rev/s. Your arms are outstretched, and you hold a heavy weight in eac

h hand. The moment of inertia of you, the extended weights, and the platform is 8.8 kg · m2.
Physics
1 answer:
bezimeni [28]3 years ago
5 0

Answer:

a) The resulting angular speed of platform is 1.38 rev/sec

b) The change in kinetic energy of the system is 53 J.

Explanation:

This question is incomplete. The complete question will be:

You stand on a frictional platform that is rotating at 1.1 rev/s. Your arms are outstretched, and you hold a heavy weight in each hand. The moment of inertia of you, the extended weights, and the platform is 8.8 kg · m2. When you pull the weights in toward your body, the moment of inertia decreases to  7.0 k g .m 2  

a) What is the resulting angular speed of the platform? Answer in units of r e v / s .

b)What is the change in kinetic energy of the system? Answer in units of J.

<h3>ANSWER:</h3>

a)

we know that:

Angular Momentum = L = Iω

From conservation of momentum:

Lo = Lf

(Io) (ωo) = (If) (ωf)

ωf = (Io) (ωo)/(If)

ωf = (8.8 kg.m²)(1.1 rev/s)/(7.0 kg.m²)

<u>ωf = 1.38 rev/sec =</u>

b)

ωf = (1.38 rev/sec)(2π rad/ 1 rev) = 8.67 rad/sec

ωo = (1.1 rev/sec)(2π rad/ 1 rev) = 6.91 rad/sec

The kinetic energy for rotational motion is given as:

K.E = (1/2)Iω²

Thus, the change in kinetic energy will be:

ΔK.E = (K.E)f - (K.E)o

ΔK.E = (1/2)Ifωf² - (1/2)Ioωo²

ΔK.E = (1/2)(Ifωf² - Ioωo²)

ΔK.E = (1/2)[(7 kg.m²)(8.67 rad/sec)² - (8.8 kg.m²)(6.91 rad/sec)²

<u>ΔK.E = 53 J</u>

You might be interested in
Alli was in the park playing on the equipment. she noticed that on the highest slide she slides down
LUCKY_DIMON [66]

Answer:

Is this answer complete????

3 0
3 years ago
Read 2 more answers
How is work involved in stopping a car?
vichka [17]
You have to move your foot to stop the car so I guess that would be considered work by moving your foot
5 0
3 years ago
Read 2 more answers
What did johannes kepler contribute to the study of planets
Nana76 [90]
Johannes Kepler was a main stargazer of the Scientific Revolution known for detailing the Laws of Planetary Motion. A stargazer, obviously, is a man who contemplates the sun, stars, planets and different parts of room. Kepler was German and lived in the vicinity of 1571 and 1630. 
Despite the fact that Kepler is best known for characterizing laws in regards to planetary movement, he made a few other striking commitments to science. He was the first to discover that refraction drives vision in the eye and that utilizing two eyes empowers profundity recognition.
4 0
2 years ago
Read 2 more answers
10. A 90 kg box is sliding across a surface at a constant velocity while experiencing a rightward applied
ANEK [815]

If the box is moving at constant velocity, net force must be zero, so:

F + fr = 0

fr = -F

<u>fr = -40 N</u>

4 0
3 years ago
Read 2 more answers
A student connects a small solar panel to a 40 a resistor to make a simple circuit. The solar panel produces a voltage of 2 0.
Nastasia [14]
<h3>Solution for the above question : -</h3>

Ohm's law states that :

  • v = ir

the terms used are :

  • r = resistance
  • v = potential \:  \: difference
  • i  = current

let's solve for electric current :

  • 2 = i \times 40

  • i =  \dfrac{2}{40}

  • i = 0.05 \: A

  • i = 50 \: mA

\mathfrak{good\:  \: luck \:  \: for \:  \: your \:  \: assignment}

8 0
2 years ago
Other questions:
  • A student uses a compressed spring of force constant 22 N/m to shoot a 0.0075 kg eraser across a desk. The magnitude of the forc
    7·1 answer
  • Why cant you feel the force attraction between mars
    11·1 answer
  • You're driving at 50 mph and then speed up to 70 mph. how much more "force" does the engine in your car have to produce to maint
    12·1 answer
  • As we increase the frequency of this light, but do not vary anything else (there may be more than one correct answer),
    13·1 answer
  • Hydraulic systems utilize Pascal's principle by transmitting pressure from one cylinder (called the primary) to another (called
    7·1 answer
  • A circuit is built based on the circuit diagram shown.
    12·1 answer
  • Why the walls of tyres becomes warm as the car moves​
    13·1 answer
  • Which term below best matches this definition - a period in European history when many educated people stressed the importance o
    9·1 answer
  • How are atoms in a molecule held together?
    9·1 answer
  • If Goku sprints and tackles a large metal crate doing 18002 J of work over the course of
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!