 Limited Time Offer: Get 2 Months of ABCmouse.com for only \$5! # Cummulative Vocabulary Words

Simple Machines

simple machines- tools that help us do work. Simple machines make work easier for us changing the amount of force (pushing or pulling) needed to do certain kinds of work.

incline plane- flat, slanted surface.

pulley- a grooved wheel with a rope around it.

screw- Inclined plane twisted in a spiral.

wedge- two inclined planes back to back.

wheel & axle- wheel and a bar that passes throught he center.

compound machine- two or more simple machines put together.

work- the use of force to make something move.

lever- a bar or a plank with a fulcrum.

Place Value / Rounding

digits- Any symbol or number (0, 1, 2, 3, 4, 5, 6, 7, 8, or 9) used to show a number

## = -Is equal to.

estimate-To find an answer that is close to the exact amount.
expanded form-A way to write numbers that shows place value of each digit
Examples: 253 = 200 + 50 + 3

> - is greater than
Example: 6 > 4
6 is greater than 4.

< - is less than
Example: 3 < 7
3 is less than 7.

numbers  - describe quantities or values

numerals-symbols used to represent numbers

periods -Each group of three digits in a place value chart; periods are typically separated by commas in a multi-digit number.
Example:  the hundreds period or the thousands period;
85,643,900 has three periods.

place value - the value given to a digit by its place in a number.

standard form- A way to write numbers that shows only its digits

Example: 3,540 standard form

## difference - The answer to a subtraction problem. Example: 8 - 5 = 3                3 is the difference.

estimation- an approximate or rough calculation, often based on rounding.

round-to drop or zero-out digits in a number and change the digit in a specified place using the following rules:-          if the digit in the first place after the specific place is 5 or more, add 1 to the digit in the specified place. This is rounding up.-          If the digit in the first place after the specified place isles than 5, do not change the digit in the specified place. This is rounding down.-          If directions do not state which place to round to, then the implication is to round to the greatest place. The only exception is rounding to the nearest whole dollar.

## Examples: 374 370 (nearest ten)                        or374 400 (nearest hundred)

Example:
12 + 7 = 19
The sum is 19.

Water Cycle

evaporation- the process in which water particles change fromliquid to gas

Solid- a state of matter that has definate shape and takes up a definite amount of space

condensation- the process in which water particles change from gas to liquid

water vapor- gas in Earth's atmosphere

liquid- a state of matter that takes up a definite amount of space but has no definite shape.

cloud- a mass of tiny droplets of condensed water in the atmosphere

precipitation- water in the atmosphere that falls to Earth as rain, snow, sleet, and hail

gas- a state of matter that does not take a definite amount of space but has a definite shape