When you kick a soccer ball the acceleration of the ball during the time your foot is contacting it will be proportional to how hard you kick it. Newton's Third Law - For every action... When you head a ball the ball is exerting the same force on your head as your head exerts on the ball.
The first law is actually two parts. One deals with bodies at rest and the other deals with bodies in motion. Inertia is the tendency of an object which is at rest to stay at rest due to gravity, friction, etc.
On earth we indirectly measure an object's mass by measuring the weight (ie the force of attraction of earth's gravity). In outer space, where gravity can't be used an "inertial balance" could be. The idea would be to apply a known force to an object and measure it's acceleration.
The math would be by Newton's 2nd Law: m = F/a
But the concept would be by his 1st Law (of inertia). The harder it is to accelerate, the more inertia or mass an object has and vice-versa.
Because accordimg 2nd law of motion
F=ma
F=force
m= mass
a=accelaration
hence less mass will cause large accelaration with same force..
you just need to concentrate on the thrust force by the hand, the frictional force between the book and the table surface.
When force is applied to the book, it is used to overcome the friction and once overcome, it causes the book to move with constant speed.
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