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
8

Disk A, with a mass of 2.0 kg and a radius of 60 cm , rotates clockwise about a frictionless vertical axle at 20 rev/s . Disk B,

also 2.0 kg but with a radius of 40 cm , rotates counterclockwise about that same axle, but at a greater height than disk A, at 20 rev/s . Disk B slides down the axle until it lands on top of disk A, after which they rotate together.After the collision, what is their common angular speed (in rev/s) and in which direction do they rotate?
Physics
1 answer:
Vladimir79 [104]3 years ago
6 0

Answer:

Explanation:

  • let m1 = 2 kg
  • r1 = 60 cm = 0.6 m
  • w1 = -20 rev/s (clockwise)

I1 = 0.5 x m1 x r1²

= 0.5 x 2 x 0.6²

= 0.36 kg.m²

m2 = 2 kg

r2 = 40 cm = 0.4 m

w2 = 20 rev/s (counter clockwise)

I2 = 0.5 x m2 x r2²

= 0.5 x 2 x 0.4²

= 0.16 kg.m²

let wf be the final angular velocity of the two disks.

Applying conservation of angular momentum ;

(I1 + I2) x wf = I1 x w1 + I2 x w2

wf = (I1 x w1 + I2 x w2) / (I1 + I2)

= (0.36 x (-20) + 0.16 x 20 )/(0.36 + 0.16)

= -7.69rev/s

The negative sign indicates the disks rotate clockwise direction.

You might be interested in
Two 5000-kg passenger cars roll without friction (one at 1 m/s, the other at 2 m/s) toward one another on a level track. They co
balu736 [363]

The combined momentum of the passengers is 5000 kgm/s.

<h3>Combined momentum of the passenger</h3>

The combined momentum of the passengers is calculated as follows;

P = mv1 + mv2

where;

  • m is mass of the passengers
  • v1 is velocity of the first passenger
  • v2 is velocity of the second passenger

P = m(v1 + v2)

P = 5000(-1 + 2)

P = 5000 kgm/s

Thus, the combined momentum of the passengers is 5000 kgm/s.

Learn more about momentum here: brainly.com/question/7538238

#SPJ1

5 0
2 years ago
A record turntable is rotating at 33 rev/min. A watermelon seed is on the turntable 4.0 cm from the axis of rotation. (a) Calcul
Annette [7]

Answer:

a) a = 0.477 m/s^2

b) u = 0.04862

Explanation:

Given:-

- The rotational speed of the turntable N = 33 rev/min

- The watermelon seed is r = 4.0 cm away from axis of rotation.

Find:-

(a) Calculate the acceleration of the seed, assuming that it does not slip. (b) What is the minimum value of the coefficient of static friction between the seed and the turntable if the seed is not to slip

Solution:-

- First determine the angular speed (w) of the turntable.

                   w = 2π*N / 60

                   w = 2π*33 / 60

                   w = 3.456 rad/s

- The watermelon seed undergoes a centripetal acceleration ( α ) defined by:

                   α = w^2 * r

                   α = 3.456^2 * 0.04

                   α = 0.477 m / s^2

- The minimum friction force (Ff) is proportional to the contact force of the seed.

- The weight (W) of the seed with mass m acts downwards. The contact force (N) can be determined from static condition of seed in vertical direction.

                   N - W = 0

                   N = W = m*g

- The friction force of the (Ff) is directed towards the center of axis of rotation, while the centripetal force acts in opposite direction. The frictional force Ff = u*N = u*m*g must be enough to match the centripetal force exerted by the turntable on the seed.

                    Ff = m*a

                    u*m*g = m*a

                    u = a / g

                    u = 0.477 / 9.81

                    u = 0.04862

8 0
3 years ago
HELP PLEASE !!
Umnica [9.8K]
If a car crashes into another car like this, the wreck should go nowhere. Besides this being an unrealistic question, the physics of it would look like this:

Momentum before and after the collision is conserved.

Momentum before the collision:
p = m * v = 50000kg * 24m/s + 55000kg * 0m/s = 50000kg * 24m/s
Momentum after the collision:
p = m * v = (50000kg + 55000kg) * v

Setting both momenta equal:
50000kg * 24m/s = (50000kg + 55000kg) * v

Solving for the velocity v:
v = 50000kg * 24m/s/(50000kg + 55000kg) = 11,43m/s

3 0
3 years ago
What effect does Earth’s spherical shape have on the amount of sunlight that reaches the equator?
vaieri [72.5K]

A

Explanation:

The earth is spherical. So it's middle part is bulgjng outside. So more sunlight will be incident on the latitude near the equator. This will heat the air and it will rise up. This will cause high pressure difference and polar disturbances.

I hope this satisfies you. I hope u will follow me and make this the brainliest answer.

5 0
3 years ago
How much Nitrogen (N) atoms are in this 3NH4Cl?
mihalych1998 [28]

Answer:

3

Explanation:

7 0
3 years ago
Other questions:
  • How is our planets giant,thermohaline system of warm and cold water like a massive convection current
    5·1 answer
  • two vehicles have a head on collision. one vehicle has a mass of 3000 kg and moves at 25 m/s while the second vehicle has a mass
    15·1 answer
  • How much kinetic energy does Bryan have?
    13·1 answer
  • A diver wants to jump from a board, the initial height is 10 meters and he wants to reach a horizontal distance of 2 meters. Wha
    5·1 answer
  • Sugar is made of carbon, hydrogen, and oxygen atoms.Sugar is
    9·1 answer
  • water flows in a pipe of a terminal of A1=0.02 m2 with a speed of V1=2 m/s. At the second end of the pipe A2=0.04 m2, the speed
    13·1 answer
  • ______is the amount of matter in an object. It does not change regardless
    15·1 answer
  • THE RIGHT ANSWER WILL RECEIVE A BRAINLESS AND POINTS AND THANKS!!! THE RIGHT ANSWER WILL RECEIVE A BRAINLESS AND POINTS AND THAN
    12·2 answers
  • What is the wavelength of light falling on double slits separated by 2.00 μm if the third-order maximum is at an angle of 60.0∘?
    15·1 answer
  • Two plane waves of the same frequency and with vibrations in the z-direction are given by c (y, t) = (2 cm) cos a p 4 cm y - 20
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!