If there is no net force acting on a body, it will continue in its state of rest or will continue moving along a straight line with uniform speed.
#2. Law of Acceleration.
The effect of an applied force is to cause the body to accelerate in the direction of the force. The acceleration is in direct proportion to the force and in inverse
proportion to the mass of the body.
#3. Law of Interaction.
When one body exerts a force on another, the second body exerts on the first a force of equal magniitude in the opposite direction.
Answered by: Richard Morgan
'The strength and weakness of physicists is that we believe in what we can measure. And if we can't measure it, then we say it probably doesn't exist. And that closes us off to an enormous amount of phenomena that we may not be able to measure because they only happened once. For example, the Big Bang. ... That's one reason why they scoffed at higher dimensions for so many years. Now we realize that there's no alternative... '