How Does Mass Affect Velocity

Detailed Explanation of Discrepant Consequence

This is a simple demonstration that tin foster discussion of many physics topics.

Begin by standing on a desk, belongings a book and an open piece of newspaper. Ask "which will hitting the footing offset if I drop them?" Typically, students volition answer the book. Ask why, the answer you will probably get is considering "the book is heavier." Then, crumple upward the paper (usually to remarks such as "cheater") and drib them. Some follow upward questions might exist...

Does crumpling the newspaper add mass to it?
When the newspaper is not crumpled does its mass make information technology fall faster?
What makes the paper fall more than slowly when it is not crumpled? (Note here y'all are leading students thought toward air resistance)
What force makes things fall toward the ground?

This demonstration can be followed upwardly with discussions on Last Velocity to talk nigh counterbalanced and unbalanced forces.

This can also be followed up with a give-and-take of projectile motion with the classic question:

"If a bullet is shot frontwards parallel to the ground without annihilation in its style, and at the exact same moment some other bullet is dropped from the same peak, which bullet will hit the footing showtime?" (Both bullets hit the basis at the same time since gravity is the only force pulling them down)

Projectile Motion Sit-in

Set-up two pennies and a ruler on a table as in the picture below.
Hit the ruler as shown, picket and listen to which penny falls kickoff. (both should hit the ground very close to the same time)

Standards

8th Class

2b. Students know when an object is bailiwick to 2 or more forces at once, the result is the cumulative effect of all the forces.

2d. Students know how to place separately the two or more forces that are acting on a single static object, including gravity, elastic forces due to tension or pinch in thing, and friction.

2g. Students know the role of gravity in forming and maintaining the shapes of planets, stars and the solar organisation.

Physics

1f. Students know applying a force to an object perpendicular to the direction of its motion causes the object to change direction but not speed (east.g., Earth's gravitational force causes a satellite in a circular orbit to alter direction simply not speed).

Questioning Script

Prior noesis & experience:

Feathers autumn slower than heavier objects.
Parachutists fall slower when the parachute is open.
Heavy objects push with greater force on your mitt.
You can feel a force on your hand if yous place it out the window of a moving machine.

Root question:

Which falls more quickly in complimentary fall, a feather or a hammer? (Meet answer hither.)
Does mass alter the acceleration of the object if gravity is the only forcefulness acting on it?
If you lot shoot a bullet parallel to the ground and at the exact aforementioned moment, from the exact aforementioned elevation, which will striking the basis get-go? (Assume the bullet does not hitting anything)
What makes a feather fall slower on world than a hammer?

Target response:

Both objects fall at the same speed.
Mass does not affect the speed of falling objects, assuming there is only gravity acting on it.
Both bullets will strike the footing at the same time. The horizontal force applied does not affect the downward move of the bullets -- only gravity and friction (air resistance), which is the aforementioned for both bullets.
Air resistance makes a plume fall slower.

Common Misconceptions:

Objects with a greater mass will fall faster (with a greater acceleration?)
An objects frontward motility will modify the rate at which objects fall.

References & Links:

Gratuitous Autumn vs Air Resistance:
http://world wide web.glenbrook.k12.il.us/gbssci/phys/Grade/newtlaws/u2l3e.html

Applet on Projectile Motion:
http://galileo.phys.virginia.edu/classes/109N/more_stuff/Applets/ProjectileMotion/jarapplet.html
http://www.walter-fendt.de/ph11e/projectile.htm