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
Tpy6a [65]
3 years ago
7

The 0.4-lb ball and its supporting cord are revolving about the vertical axis on the fixed smooth conical surface with an angula

r velocity of 4 rad /sec. The ball is held in the position b = 14 in. by the tension T in the cord. If the distance b is reduced to the constant value of 9 in. by increasing the tension T in the cord, compute the new angular velocity and the work W1-2 done on the system by T
Physics
1 answer:
solong [7]3 years ago
3 0

Answer:

Explanation:

In the whole process , angular momentum will be conserved because no external torque is acting on the system . The radius of circular path is reduced so angular velocity will be increased

I₁ x ω₁ = I₂ x ω₂

m r₁² x ω₁ = m r₁²ω₂

r₁² x ω₁ =  r₂²ω₂

ω₂ = r₁² x ω₁  /  r₂²

= ( 14 x 14 x 4) / ( 9 x 9 )

= 9.68 rad /s

Work done

= increase in rotational kinetic energy

= 1/2 x I₂ ω₂² - 1/2 x I₁ ω₁²        ( I = m r² )

=  1/2 x .4 x .454 x( 9 x 2.54 x 10⁻² x 9.68 )² - 1/2 x .4 x .454 x( 14 x 2.54 x 10⁻² x 4 )²

=   .4446 - 0.1837

= .261 J .

=

You might be interested in
The resistance, R, of a wire varies directly as its length and inversely as the square of its diameter. If the resistance of a w
lbvjy [14]

R is proportional to the length of the wire:

R ∝ length

R is also proportional to the inverse square of the diameter:

R ∝ 1/diameter²

The resistance of a wire 2700ft long with a diameter of 0.26in is 9850Ω. Now let's change the shape of the wire, adding and subtracting material as we go along, such that the wire is now 2800ft and has a diameter of 0.1in.

Calculate the scale factor due to the changed length:

k₁ = 2800/2700 = 1.037

Scale factor due to changed diameter:

k₂ = 1/(0.1/0.26)² = 6.76

Multiply the original resistance by these factors to get the new resistance:

R = R₀k₁k₂

R₀ = 9850Ω, k₁ = 1.037, k₂ = 6.76

R = 9850(1.037)(6.76)

R = 69049.682Ω

Round to the nearest hundredth:

R = 69049.68Ω

8 0
3 years ago
GIVING BRAINLIEST PLEASE HELP!!
OLga [1]
A. because I had this question yesterday.
3 0
3 years ago
If a train travels at a speed of 40 km/h for 3 hours, how far will it travel
VikaD [51]
120 km/3 hours. 40/1=?/3 1x3=3 hours so 40x3=120 km
8 0
3 years ago
Read 2 more answers
What is the uses of echoes​
Anestetic [448]

Answer:

Echoes are the reflection of sound from relatively flat object that is far enough away that you can discern the time difference. Echoes are used to measure distance, velocity, and the shape of objects. Echoes off gratings result in an unusual pinging sound

6 0
3 years ago
How do we determine the age of rocks and other geologic features?
Mamont248 [21]

Answer:To establish the age of a rock or a fossil, researchers use some type of clock to determine the date it was formed. Geologists commonly use radiometric dating methods, based on the natural radioactive decay of certain elements such as potassium and carbon, as reliable clocks to date ancient events.

Explanation:

4 0
3 years ago
Other questions:
  • What is matter made of ? Will mark as brainliest to answer
    15·2 answers
  • Fusion and fission are both processes that involve which fundamental force? to ask? A. gravitational B. weak nuclear C. electrom
    13·1 answer
  • PLZ HELP ME ASAP 30 POINTS
    6·1 answer
  • A 16 N force is applied to an object and 96 J of work is done. How far was the object moved?
    13·2 answers
  • Which of the following is not a reason fluorescent lamps are advantages over incandescent lamps?
    11·1 answer
  • Convert 3 hours 21 minutes to decimal hours.
    9·1 answer
  • . A magnetic field has a magnitude of 0.078 T and is uniform over a circular surface whose radius is 0.10 m. The field is orient
    15·1 answer
  • A turntable of radius R1 is turned by a circular rubberroller of radius R2 in contact with it at their outeredges. What is the r
    7·1 answer
  • How many significant figures are in 73,102L
    7·1 answer
  • A student sits on a pivoted stool while holding a pair of weights. The stool is free to rotate about a vertical axis with neglig
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!