user
A wheel of diameter 1meter rotates with an angular velocity of 10rad/sec. Calculate the difference between the linear velocity of a point on its rim and that of a point 200mm from the axis of rotation
alphonsio

The difference between the linear velocities is 3 m/s.


To find the linear velocities of a point on the rim and a point 200 mm from the axis of rotation, we need to use the relationship between linear velocity ( vv ) and angular velocity ( ω\omega ):

v=rωv = r \cdot \omega

where:

  • vv is the linear velocity,
  • rr is the radius at which the point is located,
  • ω\omega is the angular velocity.

Step 1: Calculate the linear velocity at the rim

Given:

  • Diameter of the wheel = 1 meter, so the radius r1r_1 = 0.5 meters (since radius is half the diameter),
  • Angular velocity ω\omega = 10 rad/sec.

The linear velocity at the rim ($ v_1 $) is:
v1=r1ω=0.5m10rad/sec=5m/sv_1 = r_1 \cdot \omega = 0.5 \, \text{m} \cdot 10 \, \text{rad/sec} = 5 \, \text{m/s}

Step 2: Calculate the linear velocity of a point 200 mm (0.2 meters) from the axis of rotation

Given:

  • Distance from the axis r2r_2 = 0.2 meters.

The linear velocity at this point ($ v_2 $) is:
v2=r2ω=0.2m10rad/sec=2m/sv_2 = r_2 \cdot \omega = 0.2 \, \text{m} \cdot 10 \, \text{rad/sec} = 2 \, \text{m/s}

Step 3: Calculate the difference between the velocities

The difference between the linear velocities is:
Δv=v1v2=5m/s2m/s=3m/s\Delta v = v_1 - v_2 = 5 \, \text{m/s} - 2 \, \text{m/s} = 3 \, \text{m/s}

Therefore, the difference between the linear velocity of a point on the rim and that of a point 200 mm from the axis of rotation is 3m/s3 \, \text{m/s}.