Pg 696
1. Read figure 11, where is there more speed?
2. Compare your drawing between a billiard and
bowling ball as it falls at the same time and height.
3. Any two objects dropped at the same height will
not depend on weight but on ________
.
Pg 696
1. Read figure 11,
where is there
more speed?
The speed is at
the bottom
where there is
more spacing
2. Compare your
drawing between a
billiard and
bowling ball as it
falls at the same
time and height.
2.
3. Any two
objects dropped
at the same
height will not
depend on
weight but on
___
the gravitational
pull of those
objects.
Pg 696
1. Read figure 11, where is there more speed?
Explain.
2. Draw the billiard ball in your journal. Then
draw a bowling ball next to it as if it was
dropped at the same height with the billiard
ball.
3. Any two objects dropped at the same height
will not depend on weight but on ___
the gravitational pull of those objects.
Do Now- Mass versus Weight
1. On page 696, How are mass and weight
different?
a. Gravity is a pull
____________________
.
on a object due to its mass.
of matter in an object.
b. Mass is the amount
_____________________
c. Therefore mass ___
never changes.
d. Weight is the measure of _______________
the gravitational pull on the object.
e. Therefore if gravity increases, weight also
increases
___ .
Copy in your journal. Class Notes
1. Formula is
weight (N) = mass (kg) X gravity (9.81 m/s2)
kg * m/s2
2. The unit for weight is ___
3. Given the gravitational force on Earth =
9.81 m/s2
4. Acceleration is an increase
___
in rate or speed of
something.
5. If an object has a mass of 10kg. What is its
weight? Give correct units.
10 kg X 9.81 m/s2 = 98.1 N
10. The mass of your motorcycle is 250 kg.
What is:
a. Its weight on Earth in Newton?
b. its weight on the moon?
c. the mass of your motorcycle on the
moon?
11. Somewhere you have a place a 7.5 kg
pumpkin on a spring scale. If the scale reads
78.4 Newton, what is the acceleration due to
gravity at that location? Show work.
Do Now
1. An increase in
gravitational
force depends
on two
factors:
increase in
a. An ___
mass
b. The shorter
___
the distance
between two
objects.
2. If these letters represent stars, which pair of
stars have the most gravitational attraction to
one another:
Bigger case letters have more mass than lower
case letters.
A….a
A….A
Circle
this pair
a….a
Do Now1a. Find the reading on the triple beam balance:
see picture
b. see picture
2. If your agenda pad has a mass of 35 grams,
what is its weight?
3. If you take your agenda pad on the moon,
what is its weight and mass?
Do Now1a. Find the reading on the triple beam balance:
30+ 5 = 35grams
b. Find the reading of the triple beam balance:
60+100+1+ 0.4 = 161.4 grams
2. If your agenda pad has a mass of 35 grams,
what is its weight?
weight = mass X gravity
35g =
kg
= .035 kg X 9.81 m/s2
1000g
= 0.34 N
3. If you take your agenda pad on the moon,
what is its weight and mass?
3. If you take your agenda pad on the moon,
what is its weight and mass?
Weight is less than 0.34 N because there is
less gravity on the moon.
Mass stays the same; 35 grams
Plotting a Line Graph
1. Label your X axis as the gravitational
acceleration. Do not plot for the Sun.
2. Label your Y axis as the weight of journal.
3. Plot your graph and give it a title.
4. What can you infer about the mass of the
objects and gravity?
5. How does weight depend on gravity?
3. Find the reading for the ruler:
1+ 0.5 = 1.5 inches
1. ___
is the measurement for the amount
of space that an object or substance occupies.
2. We measure the volume of a solid by using a
___
.
length X width X height
1. Volume
___
is the measurement for the amount
of space that an object or substance occupies.
Volume of a liquid
Volume of a solid
Formula is length X width X
height
1. Volume
___
is the measurement for the amount
of space that an object or substance occupies.
2. We measure the volume of a solid by using a
metric ruler .
___
3. Find these two
measurements. See
next slide.
length X width X height
3. Find these two measurements. 1.5 cm
3. Find these two measurements. 3.8 cm
Table #1
mass
weight
Unit
kilogram
Newton
Equipment
used
balance
spring scale
Table #2
Earth
1.60 m/s2
gravity on
moon
25.9 m/s2
gravity on
Jupiter
Mass of mug
1 kg
1 kg
1 kg
Weight of
mug
9.8 N
1.6 N
25.9 N
Reflections
date
1. Do you think we needed two labs to
understand the difference between mass and
weight? Why or why not?
1. If an object travels from Earth to the moon,
what would happen to the its mass, weight, and
volume?
2. If Mr. Hooker was standing next to Ms. Jen, in
physics sense, what would happen to Ms. Jen?
Explain.
3. Why can’t we see this gravitational pull?
Do NowIn summary:
1. Write the formula for weight and include units.
2. This means as gravity increases, weight also ___.
3. ___ never changes because it does not depend on
gravity.
4. However there is a greater gravitational force with
___ masses.
5. There is also ___ gravitational attraction between
objects that are closer together.
1. Write the formula for weight and include
WEIGHT = MASS x GRAVITY
units.
N = kg
X m/s2
2. This means when gravity increases, weight
increases .
also ___
3. mass
___ never changes because it does not
depend on gravity.
4. However there is a greater gravitational force
with ___
larger masses.
more gravitational attraction
5. There is also ___
between objects that are closer together.
Massive Confusion wkt
write on bottom margin in handout
mass
triple beam balance
weight
kg or g
spring scale
N
1. “Oh no, this can’t be right. How my weight can
change from 95 kilograms to 90 kilograms.”, Fred
N
shouted.
N
2. If I go far enough away from the Earth’s surface, I
will get to a place where my mass will be almost zero.
weight
3. An object of 200 kg on the surface of the Earth
should still measure 200 kg in the orbiting station
space station. true
4. In the space station, I would use a triple beam
balance to find the weight of an object.
mass
5. Bridgett placed a tennis ball on the triple
beam balance of 250 grams. Naturally, she could
expect the same result on the moon. true
6. Food is sold in the supermarket by weight- for
example, $2.50 for a kilogram of sugar.
N
4. In the space station, I would use a triple beam
balance to find the weight of an object.
mass
5. Bridgett placed a tennis ball on the triple
beam balance of 250 g. Naturally, she could
expect the same result on the moon. true
6. Food is sold in the supermarket by weight- for
example, $2.50 for a kilogram of sugar.
N
7. On the surface of the moon, the weight of a 100 g
mass is between 0.1 N and 0. 2 N. true
8. Due to the gravitational pull of different terrains,
my weight in New Jersey is 100 kg while in Los
Angeles it was 101 kg. N
weights
9. Galileo was right. Two different masses of rocks,
dropped from the same height can land on the
ground at the same time.
10. The amount of gravitational pull of the Earth
towards the Sun depends on the weight of the
planet. mass
11. In lab, springs and rubber bands were used
to find the mass of the metal sinkers.
weight
12. In lab, the unit used to measure weight of
objects is Newton. true
13. A triple beam balance is used to find the
weight of objects.
mass
14. It doesn’t matter which planet you go to
because the mass of an object will never
change. true
15. My weight on the moon is less than on Earth
since there is less gravity on the moon.
true
Do Now
1. All object on Earth have weight as they
experience a force of gravity that is directed
downwards towards the center of the Earth.
2. If the unit for weight is
Do now1. You are familiar with the use of newton (N).
But what does a newton feel like? Now lift
these:
a) How much weight is a 250 gram stapler? 2.5 N
25 N
b) 2.5 kg brick?
c) 7 kg chair?
70 N
Force = 500
(P- 50) where P = pressing point of
you finger and unit for Force is
Newton
ex: if you press your finger at 100 cm on the
metric ruler then the equation is:
Force = 500
(100-50)
Force = 10 N
Lab1. Part A, place a 1 kg block on the 45 cm and press
your finger on the 100 cm mark.
Lab
Part d- place your finger at the 60 cm mark
Lab
Part f
Use the
formula
given