Fill in the blanks.
(1) Newton’s first law gives the idea of ……… .
(2) By Newton’s second law , the acceleration is directly proportional to ……… .
(3) Newton’s third law express the idea of ………. .
(4) Action force and reaction force cannot ……… out each other.
(5) Force has both magnitude and ……. .
(6) Force is a ……… quantity.
(7) The SI unit for force is ……….. .
(8) Mass is a measure of ………. .
(9) The attracting force of the earth acting on a body is defined
.A physical quantity must be expressed with its number and ……….. . 1.unit