Internal forces between two particles are
Equal in magnitude only
Equal in magnitude and directions both
Equal vectors
None of the above
Internal forces-
Internal forces are all the forces exerted by various particles of the system on one another . Internal forces between two particles are equal in magnitude and opposite in direction.
External forces-
External forces are the forces that we have to apply on the object/system from outside to move or stop an object/system.
So, option 1 is correct
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