Determination for the modal age level for the grades IV and VI of the difficulty of the principle: a body at rest remains at rest, and a body in motion continues to move at constant speed along a straight line, unless the body is acted upon in either case by an unbalanced force

Jackman, Robert H.2015-03-102015-03-1019521952b14703361https://hdl.handle.net/2144/10665Thesis (Ed.M.)--Boston Universityen-USBased on investigation of the BU Libraries' staff, this work is free of known copyright restrictionsDetermination for the modal age level for the grades IV and VI of the difficulty of the principle: a body at rest remains at rest, and a body in motion continues to move at constant speed along a straight line, unless the body is acted upon in either case by an unbalanced forceThesis/Dissertation