Science lesson 1 chapter 2

STUDY STUDY STUDY STUDY STUDY A+ A+ A+ A+ A+

You pull objects around you with what?

Forces

Forces are any…

Pulls or pushes on an object

Forces between objects that touch are called

contact forces

Forces between objects that don’t touch are called

non contact forces

What are some Non contact forces

Gravity and magnetic forces

Forces have strength and direction, just like

velocity and acceleration

The more mass an object has

the more gravity it pulls on its surroundings with.

The farther apart an object is from other objects,

the less gravity it pulls on its surroundings with.

Mass is measured with what

Kilograms

In the Metric system what is weight measured by

Newtons

Why dont object have weight in space?

Because there is no gravity

What is friction caused by

microscopic dips and bumps in surfaces of things that touch each other, and get stuck when they slide past each other.

What does Atoms and molecules present in all surfaces

electric charges that attract and slow the sliding of one object against another.

How do you reduce friction

 lubricant such as soap or motor oil.

what does  lubricant such as soap or motor oil do to friction?

It fill in some of the microscopic dips and bumps present in surfaces that touch, making sliding easier.