A dog travels 3m East and then 4m West, what is his displacement?

his displacement is 5m

Explanation:

A is the stage at which a man starts walking. He's walking 4 m north, i.e. AB, then going 3 m east, i.e. BC. The displacement is the connecting straight line between the original and the final position. The displacement is thus the AC hypotenuse of the right-angle triangle. By applying the theorem of hypotenuse, we get  

⇒displacement=16+9−−−−−√=25−−√=5m

car stops. he keeps going = he has inertia

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force