An object of mass 1 kg is traveling with a constant speed of 10 m/s in the positive x-direction.
Consider case 1 in which the object above comes to a stop in 1 second.
Consider case 2 in which the same object comes to a stop in 10 seconds instead of 1 second.

Which case had the bigger change in momentum?

a. case 1

b. case 2

c. both cases have the same change in momentum

d. it cannot be determined

c. both cases have the same change in momentum

Explanation:

Momentum is a quantity used to measure the motion of a moving body, it can be expressed as;

p = mv

Where p = momentum

m = mass

v = velocity

Change in momentum of an object of the same mass can be expressed as

∆p = m∆v 1

From equation 1, since cases 1 and 2 both have the same mass, initial velocity and final velocity.

m = 1kg

v1 = 10m/s

v2 = 0

∆v = 10-0 = 10m/s

∆p = 1kg × 10m/s

∆p = 10kgm/s

Therefore, both cases have equal change in momentum ∆p = 10kgm/s.

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.

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form