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After a cannonball is fired into frictionless and gravity less space, the amount of force needed to keep it going with a constant velocity is-

After a cannonball is fired into frictionless and gravity less space, the amount of force needed to keep it going with a constant velocity is- Correct Answer Zero, since no force is requires to keep it moving. 

OPTION (4)

CONCEPT:

  • According to Newton's first law of motion, an object in motion stays in motion until acted upon by an unbalanced force.
    • With no friction in space to unbalance the cannonball, it will continue to keep going.
      • That object will remain at rest or in motion until an external force is applied.

EXPLANATION:

  • Frictionless space is defined as free space where no external force like gravity work.
    • This is called free space 
      • Hence, a cannonball is fired into frictionless space,
      • Because it is a frictionless surface it will keep going with the constant velocity

Additional Information

  • A force is a push or pulls upon an object
  • Whenever there is an interaction between two objects,
  • There must be a force act upon each of the objects.

Force = m . a   

where m is called  mass and a is called acceleration

  •  Unit of Force is defined as Newton 
  • The newton is named after Isaac Newton.

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