### What happens to frictional force as you continue to push an object?

It remains constant but at a lesser level once the object is moving.

### ways to increase friction

increase the weight of the object, rough surface, move surfaces against each other, etc.

### ways to decrease friction

wheels, decrease the weight of the object, smooth surface, resist movement between surfaces, etc.

### Weight

the measure of the downward pull of gravity; changes depending upon where you are in the universe

### Terminal Velocity

the point at which an object can no longer accelerate; air resistance meets gravity

### How do objects orbit?

The balance between the mass of two objects and the distance of the two objects are perfect.

### What three things does friction depend upon?

types of surfaces, motion of surfaces, how hard the surfaces are pushing together

### If I drop a math book and a novel at the same time, which will be most affected by air resistance?

The math book, because its surface area is bigger. Gravity will act the same on both of them but air resistance will want to push the math book up with more force.

### How does your weight and mass on Earth compare with your weight and mass on Jupiter? Why?

Because Jupiter has so much more mass than Earth, it has much stronger gravity, so I would weigh a lot more. My mass is the same, because the amount of matter in me hasn't changed.

### How does gravity, terminal velocity, and air resistance work on a penny when it is dropped from a 50 story building?

Gravity pulls the penny down, but air resistance pushes the penny up against gravity. At a certain point, air is pushing up on gravity so much that gravity can't accelerate anymore. This is when the penny reaches terminal velocity.