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Worksheet(Multiple Choice Questions)

1.A man on Earth weights 100kg.If his location is at the Earth's Moon now,what would be his weight
A)100kg
B)100N
C)1000kg
D)1000N

3.A newton is equivalent to one:
a) kg m /s
b) kg m2/s
c) kg m/s2
d) kg m2/s2

4.If you were to travel to a different planet:
a) your weight and mass would both change.
b) your weight and mass would not change.
c) your weight would change but your mass would not change.
d) your weight would not change but your mass would change.

5.When you stand on a scale with both feet it reads 80 kg. If you stand on one foot it will read
a) 80 kg.
b) less than 80 kg.
c) more than 80 kg.

6.John weighs 100 N on Earth and Mary weighs 100 N on the Moon.
a) John’s mass is greater than Mary’s.
b) Mary’s mass is greater than John’s.
c) John and Mary have the same mass.

7.which of the answer is correct for mass
a)it is measured in newton
b)it is a vector quantity
c)it's sl unit is N
d)it is the amount of substances in a body

8.what is a instrument to measure weight
a)micrometer screwgauge
b)ruler
c)spring balance
d)beam balance

9.A piece of wood named X is put into a beaker of water.Another piece of wood,made of same material but is trice the sizeis also put into the same beaker.What would be the most appropriate location it would be?
a)same location as X
b)lower then X
c)higher then X

10.A radio is taken from moon back to earth.Which of the following descrbes the changesto its mass and weight correctly?
a)both mass and weight increase
b)mass have no change,weight decrease
c)mass decrease,weight have no change
d)mass no change,weight increase

The density of a material is defined as its mass per unit volume. The symbol of density is ρ (the Greek letter rho).

There are two kinds of density, "weight density" and "mass density". We will only use mass density and when we say: "density", we will mean "mass density".

Density is mass per volume. Lead is dense, Styrofoam is not. The metric system was designed so that water will have a density of one gram per cubic centimeter or 1000 kilograms per cubic meter.
Lead is about 10 times as dense as water and Styrofoam is about one tenth as dense as water.

here is a link for further explaination of density

http://www.youtube.com/watch?v=rxb_6UANXqU

here is a link of a animation on how density of an object causes it to float or sink in water.

http://www.youtube.com/watch?v=KALbn7kRx_Y

How to distinguish between mass and weight?

this is a video distinguishing difference between Mass and Weight
http://www.youtube.com/watch?v=grWG_U4sgS8

weight=massxgravitational field strength

(w=mg)

The weight of an object can be measured using:

Gravitational Field Strength,g
Defined as the gravitational force acting per unit mass on an object.

On Earth the gravitational feild strength is about 10N/kg

1kg of mass experiences a force of 10N due to Earth's gravitational pull.

gravitational field strength is equivalent to acceleration of free fall

Question:why would your weight decrease if you are on the moon
Answer:because moon has a lower gravitational field strength.Infact,you would be 1/6 of your's Earth weight on the moon

Gravity is an attractive force. This doesn't mean it's pretty. What "attractive" means is that an object's gravity pulls other objects toward it.
The Earth's gravity naturally pulls us, and everything else, toward the center of the planet, which keeps us from drifting off into space.

The force of gravity is the force with which the Earth,Moon,or other massive body attracts an object towards itself.
The Earth isn't the only thing that has gravity. In fact, every single object in the universe has gravity.

Gravitational field is a region in which a mass experiences a force due to gravitational attraction.

here is a video showing what is gravity

http://www.youtube.com/watch?v=Uy3nATe85Kg