Unite one (lesson 1)

Unite one (lesson 1)

Mass: is the amount of matter that the object contains.
Gram = the mass of paper clips It's unite is gram (g)
Kilogram (kg) = 1000 gram = 1 liter of water
Measuring tools:
1-Two bans common balance 2-Sensitive balance with two bans
3-One ban balance with pointer 4-Digital one ban balance

Activity1: how to measure the mass

Tools: two bans balance- known mass weight- the object you want to measure it's mass
Steps:
Put the balance horizontally on a stable shelf not vibrating
Make sure that the balance is totally clean
Put the object in one of the bans
Put the weights in the other ban till the bans take the same place
The total weights are the mass of the object

*notes: The mass doesn’t change from place to another
The bodies mass on earth equal their mass on moon


Weight: is the earth attraction force to the body
Its direction is earth center
It's unite is Newton
Newton: is weight of 100 gram of mass
Measuring tools: Spring balance

Activity 2: who to measure the weight

Tools: Spring balance- the body measure
Steps: hold the spring balance then hang the body
Let it get down slowly till it is stable then reed the balance
This is the body weight with Newton


The factors that affect the weight:

1- The body mass:
The body weight increase by its mass increasing
Bring different masses of bodies and measure their weight
4 3 2 1 Mass (kg)
40 30 20 10 Weight(N)

Weight (N) = mass (kg) x 10
2- Which planet the body is on
As the planet mass increases its attraction force increases and the body weight increases

**body weight on moon = 1/6 body weight on earth

3- The distance between the body and the planet center

By increasing the distance the attraction force decreases so the weight decreases
weight mass Points
the earth attraction force to the body the amount of matter that the object contains definition
Newton Gram- kilogram Measuring unite
Spring balance Two ban balance Measuring tool
Planet center direction non Effecting direction
Change No change Change place affecting

Exercises

A) Complete:
1. The measuring unite of mass is……….. Or ……….. While the weight measuring unite is ………………..
2. The mass measure using …………………. While weight measure by using.
3. The mass is a constant value doesn't change by …………………………changing
4. The body weight depending on …………………….., ……………………………..

B) Write the scientific term:
1. The amount of matter that the object contains.
2. The earth attraction force to the body
3. The measuring unite of mass and equal near a liter of water
4. Measuring unite of weight and equal near a weight of 100 gram of mass

C) Mass of body on earth = 6 kg, calculate its weight on earth, and on moon surface.

D) Choose:
1. The measuring tool of weight is ……………….
One ban balance - two bans balance - digital balance - spring balance

2. A body weight on earth 20 Newton its mass equal………..
10kg - 20kg - 200kg - 2kg

E) Connect:
A B
The earth attraction force of body kg
The mass measuring unite Spring balance
The weight measuring unite weight
Amount of matter that the object contains. mass

F) Compare between mass and weight

G) If a body mass =30kg on earth calculate
1. Its mass on moon
2. Its weight on earth
3. Its weight on moon