Suppose that superman wants to stop earth so it does not rotate. he exerts a force on earth at earth's equator tangent to its surface for a time interval of 1 year. the mass of earth is 5.98�1024 kg, the radius is 6.37�106 m. assume that earth is a solid sphere with its mass distributed uniformly. part awhat magnitude force must he exert to stop earth's rotation?

Explanation:

We know that torque exerted by superman is given by:

  where It is earth's inertia, and αt is earth acceleration.

The inertia of a solid sphere is calculated as:

Earth's acceleration is:

Where t is the lapse of 1 year. t = 365*24*3600 = 31536000s

Solving for the acceleration and replacing the values:

Replacing this value on the torque equation:

what type of charge does it have? negative