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Gert
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Consider the Free Body Diagram:

Rotation forces

where:

  • $F$ is a driving force
  • $mg$ the weight of the wheel
  • $F_N$ a reactive force, called the Normal force
  • $F_f$ a friction force

We can now establish some force/torque balances.

In the vertical ($y$) direction, there no motion because with $\text{N2L}$:

$$\Sigma F_y=F_N-mg=0 \Rightarrow F_N=mg$$

The friction force is usually modeled as:

$$F_f=\mu F_N=\mu mg$$

As long as no slipping occurs, $\mu$ is the static friction coefficient.

Now, looking at the balance of torques about the CoG (marked as $+$) we have a net torque balance $\tau$:

$$\tau=F\lambda-F_f R=F\lambda-\mu mg R$$

As per $\text{N2L}$ (applied for rotation) this causes angular acceleration $\alpha$, in the clockwise direction:

$$\tau= I_w \alpha \Rightarrow \alpha=\frac{\tau}{I_w}$$

where $I_w$ is the inertial moment of the wheel.

Note that $\alpha=\frac{\text{d}\omega}{\text{d}t}$.

Without slipping/sliding, we can write $v=\omega R$ and also:

$$a=\alpha R$$

Or:

$$a=\frac{F\lambda-\mu mg R}{I_w}R$$

Consider the Free Body Diagram:

Rotation forces

where:

  • $F$ is a driving force
  • $mg$ the weight of the wheel
  • $F_N$ a reactive force, called the Normal force
  • $F_f$ a friction force

We can now establish some force/torque balances.

In the vertical ($y$) direction, there no motion because with $\text{N2L}$:

$$\Sigma F_y=F_N-mg=0 \Rightarrow F_N=mg$$

The friction force is usually modeled as:

$$F_f=\mu F_N=\mu mg$$

As long as no slipping occurs, $\mu$ is the static friction coefficient.

Now, looking at the balance of torques about the CoG (marked as $+$) we have a net torque balance $\tau$:

$$\tau=F\lambda-F_f R=F\lambda-\mu mg R$$

As per $\text{N2L}$ (applied for rotation) this causes angular acceleration $\alpha$:

$$\tau= I_w \alpha \Rightarrow \alpha=\frac{\tau}{I_w}$$

where $I_w$ is the inertial moment of the wheel.

Note that $\alpha=\frac{\text{d}\omega}{\text{d}t}$.

Without slipping/sliding, we can write $v=\omega R$ and also:

$$a=\alpha R$$

Or:

$$a=\frac{F\lambda-\mu mg R}{I_w}R$$

Consider the Free Body Diagram:

Rotation forces

where:

  • $F$ is a driving force
  • $mg$ the weight of the wheel
  • $F_N$ a reactive force, called the Normal force
  • $F_f$ a friction force

We can now establish some force/torque balances.

In the vertical ($y$) direction, there no motion because with $\text{N2L}$:

$$\Sigma F_y=F_N-mg=0 \Rightarrow F_N=mg$$

The friction force is usually modeled as:

$$F_f=\mu F_N=\mu mg$$

As long as no slipping occurs, $\mu$ is the static friction coefficient.

Now, looking at the balance of torques about the CoG (marked as $+$) we have a net torque balance $\tau$:

$$\tau=F\lambda-F_f R=F\lambda-\mu mg R$$

As per $\text{N2L}$ (applied for rotation) this causes angular acceleration $\alpha$, in the clockwise direction:

$$\tau= I_w \alpha \Rightarrow \alpha=\frac{\tau}{I_w}$$

where $I_w$ is the inertial moment of the wheel.

Note that $\alpha=\frac{\text{d}\omega}{\text{d}t}$.

Without slipping/sliding, we can write $v=\omega R$ and also:

$$a=\alpha R$$

Or:

$$a=\frac{F\lambda-\mu mg R}{I_w}R$$

added 56 characters in body
Source Link
Gert
  • 35.5k
  • 8
  • 62
  • 107

Consider the Free Body Diagram:

Rotation forces

where:

  • $F$ is a driving force
  • $mg$ the weight of the wheel
  • $F_N$ a reactive force, called the Normal force
  • $F_f$ a friction force

We can now establish some force/torque balances.

In the vertical ($y$) direction, there no motion because with $\text{N2L}$:

$$F_N=mg$$$$\Sigma F_y=F_N-mg=0 \Rightarrow F_N=mg$$

The friction force is usually modeled as:

$$F_f=\mu F_N=\mu mg$$

As long as no slipping occurs, $\mu$ is the static friction coefficient.

Now, looking at the balance of torques about the CoG (marked as $+$) we have a net torque balance $\tau$:

$$\tau=F\lambda-F_f R=F\lambda-\mu mg R$$

As per $\text{N2L}$ (applied for rotation) this causes angular acceleration $\alpha$:

$$\tau= I_w \alpha \Rightarrow \alpha=\frac{\tau}{I_w}$$

where $I_w$ is the inertial moment of the wheel.

Note that $\alpha=\frac{\text{d}\omega}{\text{d}t}$.

Without slipping/sliding, we can write $v=\omega R$ and also:

$$a=\alpha R$$

Or:

$$a=\frac{F\lambda-\mu mg R}{I_w}R$$

Consider the Free Body Diagram:

Rotation forces

where:

  • $F$ is a driving force
  • $mg$ the weight of the wheel
  • $F_N$ a reactive force, called the Normal force
  • $F_f$ a friction force

We can now establish some force/torque balances.

In the vertical direction, there no motion because with $\text{N2L}$:

$$F_N=mg$$

The friction force is usually modeled as:

$$F_f=\mu F_N=\mu mg$$

As long as no slipping occurs, $\mu$ is the static friction coefficient.

Now, looking at the balance of torques about the CoG (marked as $+$) we have a net torque balance $\tau$:

$$\tau=F\lambda-F_f R=F\lambda-\mu mg R$$

As per $\text{N2L}$ (applied for rotation) this causes angular acceleration $\alpha$:

$$\tau= I_w \alpha \Rightarrow \alpha=\frac{\tau}{I_w}$$

where $I_w$ is the inertial moment of the wheel.

Without slipping/sliding, we can write $v=\omega R$ and also:

$$a=\alpha R$$

Or:

$$a=\frac{F\lambda-\mu mg R}{I_w}R$$

Consider the Free Body Diagram:

Rotation forces

where:

  • $F$ is a driving force
  • $mg$ the weight of the wheel
  • $F_N$ a reactive force, called the Normal force
  • $F_f$ a friction force

We can now establish some force/torque balances.

In the vertical ($y$) direction, there no motion because with $\text{N2L}$:

$$\Sigma F_y=F_N-mg=0 \Rightarrow F_N=mg$$

The friction force is usually modeled as:

$$F_f=\mu F_N=\mu mg$$

As long as no slipping occurs, $\mu$ is the static friction coefficient.

Now, looking at the balance of torques about the CoG (marked as $+$) we have a net torque balance $\tau$:

$$\tau=F\lambda-F_f R=F\lambda-\mu mg R$$

As per $\text{N2L}$ (applied for rotation) this causes angular acceleration $\alpha$:

$$\tau= I_w \alpha \Rightarrow \alpha=\frac{\tau}{I_w}$$

where $I_w$ is the inertial moment of the wheel.

Note that $\alpha=\frac{\text{d}\omega}{\text{d}t}$.

Without slipping/sliding, we can write $v=\omega R$ and also:

$$a=\alpha R$$

Or:

$$a=\frac{F\lambda-\mu mg R}{I_w}R$$

added 7 characters in body
Source Link
Gert
  • 35.5k
  • 8
  • 62
  • 107

Consider the Free Body Diagram:

Rotation forces

where:

  • $F$ is a driving force
  • $mg$ the weight of the wheel
  • $F_N$ a reactive force, called the Normal force
  • $F_f$ a friction force

We can now establish some force/torque balances.

In the vertical direction, there no motion because with $\text{N2L}$:

$$F_N=mg$$

The friction force is usually modeled as:

$$F_f=\mu F_N=\mu mg$$

As long as no slipping occurs, $\mu$ is the static friction coefficient.

Now, looking at the balance of torques about the CoG (marked as $+$) we have a net torque balance $\tau$:

$$\tau=F\lambda-F_f R=F\lambda-\mu mg R$$

As per $\text{N2L}$ (applied for rotation) this causes angular acceleration $\alpha$:

$$\tau= I_w \alpha \Rightarrow \alpha=\frac{\tau}{I_w}$$

where $I_w$ is the inertial moment of the wheel.

Without slipping/sliding, we can write $v=\omega R$ and also:

$$a=\alpha R$$

Or:

$$a=\frac{F\lambda-\mu mg R}{I_w}R$$

Consider the Free Body Diagram:

Rotation forces

where:

  • $F$ is a driving force
  • $mg$ the weight of the wheel
  • $F_N$ a reactive force, called the Normal force
  • $F_f$ a friction force

We can now establish some force/torque balances.

In the vertical direction, there no motion because with $\text{N2L}$:

$$F_N=mg$$

The friction force is usually modeled as:

$$F_f=\mu F_N=\mu mg$$

As long as no slipping occurs, $\mu$ is the static friction coefficient.

Now, looking at the balance of torques about the CoG (marked as $+$) we have a net balance $\tau$:

$$\tau=F\lambda-F_f R=F\lambda-\mu mg R$$

As per $\text{N2L}$ (applied for rotation) this causes angular acceleration $\alpha$:

$$\tau= I_w \alpha \Rightarrow \alpha=\frac{\tau}{I_w}$$

where $I_w$ is the inertial moment of the wheel.

Without slipping/sliding, we can write $v=\omega R$ and also:

$$a=\alpha R$$

Or:

$$a=\frac{F\lambda-\mu mg R}{I_w}R$$

Consider the Free Body Diagram:

Rotation forces

where:

  • $F$ is a driving force
  • $mg$ the weight of the wheel
  • $F_N$ a reactive force, called the Normal force
  • $F_f$ a friction force

We can now establish some force/torque balances.

In the vertical direction, there no motion because with $\text{N2L}$:

$$F_N=mg$$

The friction force is usually modeled as:

$$F_f=\mu F_N=\mu mg$$

As long as no slipping occurs, $\mu$ is the static friction coefficient.

Now, looking at the balance of torques about the CoG (marked as $+$) we have a net torque balance $\tau$:

$$\tau=F\lambda-F_f R=F\lambda-\mu mg R$$

As per $\text{N2L}$ (applied for rotation) this causes angular acceleration $\alpha$:

$$\tau= I_w \alpha \Rightarrow \alpha=\frac{\tau}{I_w}$$

where $I_w$ is the inertial moment of the wheel.

Without slipping/sliding, we can write $v=\omega R$ and also:

$$a=\alpha R$$

Or:

$$a=\frac{F\lambda-\mu mg R}{I_w}R$$

Source Link
Gert
  • 35.5k
  • 8
  • 62
  • 107
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