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
Sloan [31]
3 years ago
12

If the CD rotates clockwise at 500 rpm (revolutions per minute) while the last song is playing, and then spins down to zero angu

lar speed in 2.60 s with constant angular acceleration, what is α, the magnitude of the angular acceleration of the CD, as it spins to a stop?
Physics
2 answers:
gavmur [86]3 years ago
8 0

Answer:

Explanation:

Given that,

Initial Angular velocity w=500rpm

Converting from rpm to rad/s

1rev =2πrad

1minutes =60secs

500rpm=500rev/mins

w = 500×2π/60

wi=52.36rad/s

The final angular velocity wf=0rad/s

Time to stop is t=2.6sec

We want to find angular acceleration α

Using the equation of angular motion

wf = wi + αt.

0 = 52.36 + 2.6α

-52.36=2.6α

α = -52.36/2.6

α = -20.14rad/s²

The angular acceleration is negative because it is decelerating.

Then, α=20.14rad/s²

Tems11 [23]3 years ago
8 0

Answer:

Explanation:

Given:

Initial angular velocity, wi = 500 rpm

Converting from rom to rad/s,

500 rev/min × 2pi rad/1 rev × 1 min/60s

= 52.36 rad/s

Final angular velocity, wf = 0 rad/s

Time, t = 2.6 s

Using equations of angular motion,

wf = wi + αt

α = (52.36 - 0)/2.6

= 20.138 rad/s^2

= 20.14 rad/s^2

You might be interested in
What is the atmospheric pressure 1.00 km above the surface of Venus? Express your answer in Earth-atmospheres.
EleoNora [17]

Below is an attachment containing the solution.

4 0
3 years ago
A complete circuit contains two parallel connected devices and a generator for providing the electromotive force. The resistance
irga5000 [103]
We are asked to solve and determine the magnitude of the current flowing through the first device. In order for us to have a better understanding of the problem, we can refer to the attached picture which contains electric circuit diagram. Since it the problem we are already given with an electromotive source or the voltage supply and since the two resistance is in parallel, it would clearly mean that the voltage drop in each resistance is just the same. The resistance 1 uses the 40 volts at the same time the resistance 2 uses 40 volts also. Solving further for the current, we can apply Ohm's law which V = IR where "V" represents the voltage, the "I" represents the current and "R" represents the resistance.

Such as the solution in obtaining current is shown below:
I = V / R, substitute values we have it
I = 40 volts / 1208 ohms
I = 0.0331 Amperes

Therefore, the current flowing in the first device is 0.033 Amperes or 33 milliAmperes.

6 0
3 years ago
Help? I don't know how to do this.
aliya0001 [1]

Use the definition of acceleration:

Acceleration = (change of velocity) divided by (time for the change)

The graph says:

Change of velocity = -6 m/s

Time for the change = 3 sec

So Acceleration = (-6m/s) / (3 s)

That's -6/3 m/s•s

or

-2 m/s^2

5 0
3 years ago
When a 70 kg man sits on the stool, by what percent does the length of the legs decrease? Assume, for simplicity, that the stool
allochka39001 [22]

The diameter of one leg of the stool is missing and it's 2cm.

Answer:

(ΔL/L) = 0.00729%

Explanation:

If the Weight of the man is W, the weight will be distributed equally on the 3 legs and so the reactions for each leg will be W/3 or F/3.

Now, Youngs modulus(Y) of douglas fir wood is about 1.3 x 10^(10) N/m^2. Gotten from youngs modulus of common materials.

Now, weight of man is 70kg.

Now diameter of one leg is 2cm.so radius of one leg = 2/2 = 1cm = 1 x 10^(-2)m

Area for one leg is; π( 1 x 10^(-2)m)^2 = 3.14 x 10^(-4)m

Now as stated earlier, the force on one leg is; F/3.

Now F = mg = 70 x 9.81 = 686.7N

So, force on one leg = 686.7/3 = 228. 9N

Now we know youngs modulus(Y) = Stress/Strain.

Stress = F/A while Strain = ΔL/L

Therefore Y = (F/A) / (ΔL/L)

And therefore, (ΔL/L) = F/(AY)

So (ΔL/L) = 228.9/(3.14 x 10^(-4))x(1.3 x 10^(10)) = 7. 29 x 10^(-5)

When expressed in percentage, it becomes 0.00729%

7 0
3 years ago
Barney walks at a velocity of 1.7 meters/second on an inclined plane, which has an angle of 18.5° with the ground. What is the h
Viktor [21]
The velocities and the speed build a triangle, where the 1.7 m/s are the hypotenuse and the x-velocity and y-velocity are the other sides. 

<span>So the x-velocity is: speed*cos(angle) </span>

<span>now plug in </span>
<span>x=1.7 m/s * cos(18.5)=1.597 m/s </span>


3 0
3 years ago
Other questions:
  • A mosquito flying over a highway strikes a windshield of a moving truck. Compared to the magnitude of the force of the truck on
    7·1 answer
  • Light incident on a surface at an angle of 45° undergoes diffused reflection. At what angle will it reflect?
    5·2 answers
  • 1. An object is moving to the right while a force directed to the left acts on the object. Is this force
    13·1 answer
  • 3.
    8·2 answers
  • A dentist’s drill starts from rest. After 1.46 sof constant angular acceleration, it turns at arate of 27000 rev/min.Find the dr
    9·1 answer
  • An exploding plastic egg is sitting at rest on a lab table when it explodes into two pieces. One piece goes left at 6.0 m/a, cal
    5·1 answer
  • A bicyclist is coasting straight down a hill at a constant speed. The mass of the rider and bicycle is 96.0 kg, and the hill is
    13·1 answer
  • A falcon is hovering above the ground, then suddenly pulls in its wings and begins to fall toward the ground. Air resistance is
    5·1 answer
  • What is the relationship between kinetic and potential energy of a falling object
    7·1 answer
  • WILL MARK BRAINLIEST!!!
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!