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Could somebody help with the following questions please?

1. Find the radius of the rotating flywheel:
- radial velocity Vr=0.5 m s^-1
- angular velocity w=0.5 rad s^1
- tangential acceleration at=0.5 m s^-2
- centripetal acceleration ac=-0.33 m s^-2
- tangential velocity Vt=0.65 m s^-1

2. Verify the magnitudes of:
- centripetal acceleration ac=-0.21 m s^-2
- tangential acceleration at=0.24 m s^-2
>>>>>>showing all working!
Known data:
- radial velocity Vr=0.3 m s^-1
- angular velocity w=0.4 m s^-1
- tangential velocity Vt=0.52 m s^-1
You may need answer to part 1 for some of the calculations.

3. Using the results from part 2 to calculate the magnitude and direction (as an angle in degrees in relation to the direction r) for the resultant vector a.

User Ramell
by
8.5k points

1 Answer

4 votes

Answer:

1. The radius of the rotating flywheel is approximately 0.675 meters.

2. The calculated values do not match the given values, so there might be some mistake in the given data or in the calculations.

3. The magnitude of the resultant vector (a) is approximately 0.4159 m/s^2, and its direction in relation to the direction r is approximately 14.738 degrees.

Step-by-step explanation:

let's go through each question step by step:

1. Find the radius of the rotating flywheel:

We can use the following equations to find the radius (r) of the rotating flywheel:

Centripetal acceleration (ac) is given by: ac = Vt^2 / r

Tangential acceleration (at) is given by: at = r * w^2

Tangential velocity (Vt) is given by: Vt = r * w

Radial velocity (Vr) is given by: Vr = r * w

First, let's find the radius (r) using the given tangential velocity and angular velocity:

Given:

Vt = 0.65 m/s

w = 0.5 rad/s

Using Vt = r * w, we can rearrange to solve for r:

r = Vt / w

r = 0.65 m/s / 0.5 rad/s

r = 1.3 m

Now, let's find the radius (r) using the centripetal acceleration and tangential acceleration:

Given:

at = 0.5 m/s^2

ac = -0.33 m/s^2

Using at = r * w^2, we can rearrange to solve for r:

r = at / w^2

r = 0.5 m/s^2 / (0.5 rad/s)^2

r = 2 m

Using ac = Vt^2 / r, we can rearrange to solve for r:

r = Vt^2 / ac

r = (0.65 m/s)^2 / -0.33 m/s^2

r = -1.274 m

Now, let's calculate the average radius from the three values of r:

Average r = (1.3 m + 2 m - 1.274 m) / 3

Average r = 0.675 m

So, the radius of the rotating flywheel is approximately 0.675 meters.

2. Verify the magnitudes of centripetal acceleration (ac) and tangential acceleration (at):

Given:

Vr = 0.3 m/s

w = 0.4 rad/s

Vt = 0.52 m/s

We already know the formulas for centripetal acceleration and tangential acceleration. Let's calculate them using the provided data:

Centripetal acceleration (ac):

ac = Vt^2 / r

ac = (0.52 m/s)^2 / 0.675 m

ac = 0.4016 m/s^2

Tangential acceleration (at):

at = r * w^2

at = 0.675 m * (0.4 rad/s)^2

at = 0.108 m/s^2

Now, let's compare the calculated values with the given values:

Given values:

ac (given) = -0.21 m/s^2

at (given) = 0.24 m/s^2

Calculated values:

ac (calculated) = 0.4016 m/s^2

at (calculated) = 0.108 m/s^2

The calculated values do not match the given values, so there might be some mistake in the given data or in the calculations.

3. Calculate the magnitude and direction of the resultant vector a:

To calculate the magnitude of the resultant vector (a), we can use the Pythagorean theorem as follows:

Magnitude of a (|a|) = sqrt(at^2 + ac^2)

Using the calculated values from part 2:

Magnitude of a (|a|) = sqrt((0.108 m/s^2)^2 + (0.4016 m/s^2)^2)

Magnitude of a (|a|) = sqrt(0.011664 m^2/s^4 + 0.161280256 m^2/s^4)

Magnitude of a (|a|) = sqrt(0.172944256 m^2/s^4)

Magnitude of a (|a|) = 0.4159 m/s^2

Now, to find the direction of the resultant vector (a) in degrees with respect to the direction r, we can use trigonometry:

Angle (θ) = atan(at / ac)

Angle (θ) = atan(0.108 m/s^2 / 0.4016 m/s^2)

Angle (θ) = atan(0.2686119403)

Using a calculator, we find:

Angle (θ) ≈ 14.738 degrees

So, the magnitude of the resultant vector (a) is approximately 0.4159 m/s^2, and its direction in relation to the direction r is approximately 14.738 degrees.

User PhilMasteG
by
8.0k points