Rank in decreasing order the pressure that the italicized objects exert on the surface. I. A person standing with bare feet on the floor II. A person in skis standing on snow III. A person in Rollerblades standing on a road IV. A person in ice skates standing on ice Consider a person to be the same for each of the cases. Assume that skis, Rollerblades, and ice skates are massless.

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.

the answer is 12 as i may remember

: )