A hot wheels car accelerates at a rate of 5m/s2 west. The car has a mass of 3 kg. How much force was applied to the car to produce this acceleration?
F=m*a
5m/s2 * 3kg=15 N west
Don't forget direction and Newtons!
What is the difference between heat and temperature?
Heat is the energy of a substance that comes from the speed of its molecules.
Temperature is the measure of the average speed of moving particles within a substance.
What are the 3 properties of air?
Air takes up space.
Air has weight.
Air has pressure.
Archimedes' Principle
The buoyant force applied to an object in fluid is equal to the weight of the fluid displaced by the object NOT by the weight of the object itself.
Why is it important to understand vertical alignment of the TEKS in content areas?
Each year builds on the previous year.
What is a "black box" and what is an example of one?
A black box is any system that can't be observed or touched directly and can not be completely understood, like the Earth's core.
Why didn't the blob of clay float when the boat made out of the blob wouldn't?
The boat is a clay-air system. The density of the boat is less than the density of water because of the air. The clay blob's density is greater than the buoyant force therefore the blob sank.
Scaling
the study of how size affects the relationship between weight, strength and surface area
Physical Model
can be demonstrated
Volume
space defined by length, width and height
Buoyancy
an upwards force acting on objects in fluids
ampere
metric unit used in scientific application
mass
amount of stuff in something
density
how much matter is squeezed into a given space
heliocentric
model of the universe with the Sun in the center
cc
unit of measurement for volume
second
metric unit used in everyday life
weight
force on a object due to gravity
matter
anything that has mass and volume
geocentric
a model of the universe with the Earth as the center
Gravity
a force of attraction between all masses in the universe; especially the attraction of the earth's mass for bodies near its surface
3 Things Necessary for a fire to burn
Oxygen
Fuel
Right kindling temperature
It takes 5 seconds to walk from my house northward to my neighbors 8 meters away. What is the average velocity?
V=d/t
8m/5s=1.6m/s north
Don't forget direction!
A turtle swimming in a straight line toward shore has a speed of 0.50 m/s. After 4.0 seconds, its speed is 0.80 m/s. What is the turtle's average acceleration?
A=change in velocity/time
(0.80 - 0.50) m/s / 4s = 0.075 m/s2 toward shore
Drew finishes a 132 meter race in 18 seconds. What is his average speed?
d/t
132m/18s = 7.3 m/s
Automobile seat belts are necessary for safety because of a passenger's __________.
Inertia
Exactly 2 g of steel wool was placed in a 100 g glass jar. After 50 g of water was added to the jar, the lid was sealed tightly. One week later, the steel wool had turned completely to rust. What was the mass of the jar and its contents after 1 week?
152 g
Air flows from areas of ________ pressure to areas of _______ pressure.
Higher, lower
A straight line distance covered during a certain amount of time describes an object's _________.
speed
The Fortune Telling fish curls, twists and bends in the palm of your hand because . . .
the cellophane absorbs moisture from your hand
Which 1 of Newton's laws serves as the basis for rocket travel?
3rd
According to Boyle's law, if the volume of a gas increases, the pressure increases.
False
The correct order for the colors that make up the visible light portion of the electromagnetic spectrum are . . .
ROYGBIV
A marshmallow (a colloid) is an example of a _____ in a _____.
gas, solid
If we have 2 balls that are 1 m apart and we tripple the original distance, the gravitational force decrease to _______ its original value.
32 = 9 = 9/1 = 1/9
Held in place by the force of gravity are the top 2 gases in our atmosphere. They are ____% oxygen & ____% nitrogen.
21, 78
The force of gravity between 2 objects depends on their mass and the distance between the 2 objects.
True or False
True
___________ is defined as a force acting through distance.
Work
Which 1 of the following is NOT true about carbon dioxide?
it is odorless
it is heavier than air
it is colorless
it supports combustion
it supports combustion
In order to cause something to move in a circular path, it is necessary to provide . . .
centripetal force
You want to know if an egg is raw or hardboiled without breaking it. One way to determine this is to . . .
spin the egg and observe its behavior.
At standard sea level the atmospheric pressure is ____ pounds per square inch.
14.7
The winner of the shot put event in the Olympics is the person who best uses . . .
Newton's 2nd law
Which of the following are properties of both liquids and gases, but not of solids?
The force of gravity on the moon is less than on the Earth because the moon's mass is smaller than the Earth's.
True or False
True
Marshmallows will expand in a syringe because you change the gas volume in them by changing the pressure inside the syringe. True or False
True
In the activity where the alka seltzer was dissolved in a huge brandy snifter, what caused the match to go out when it was lowered into the snifter?
carbon dioxide had formed in the container.
Which of the following is an example of acceleration?
1. A car speeds up
2. A car slows down
3. A car travels in a straight line at a constant speed
4. A car travels at a constant speed and turns left
1, 2 & 4 only
Heat energy is always transferred from cooler to warmer objects in an effort to reach equilibrium. True or False
False.
It transfers from warmer to cooler.
In the egg in a bottle activity, when the flame went out the pressure inside the bottle was ____ the pressure outside.
lower than
Newton's 2nd law of motion can be expressed as F = ma. True or False
True
The center of gravity for a male is generally lower than in a female because males are larger in the pelvic area. True or False
False
The process of changing from a gas to a liquid is called ______ and changing from a liquid to a solid is called _______.
condensation, freezing
Changing the mass of an object can change its center of gravity. True or False
True
Short wavelengths have lower frequencies and greater energy.
False
They have higher frequencies and greater energy.
_______ is the transfer of heat from 1 molecule to another by direct contact.
Conduction
Rotational inertia is only determined by the distribution of the mass of the object. True or False
False
Your vestibular sense indicates body orientation and is your body's biological gravity detector. Which one of the vestibular organs detects linear acceleration of the head?
Otolith organs
The speed of light is slower at 186,000 miles per second, that the speed of sound. True or False
False
To find the balance point for an irregular object you must use a ________.
plumb bob
The expression "the air is thin" refers to the higher you go in altitude the more gas molecules there are and the harder it is to breathe. True or False
False
If the center of gravity of an object is outside its support base it can still remain upright. True or False
False
Energy
the capacity to do work
Potential Energy
stored energy; energy ready to do work
m (kg) * gravitational acceleration (9.8 m/s2) * height (m)
PE = mgh
i.e. mouse trap
Kinetic Energy
the energy of motion; depends on mass and speed
KE = 1/2 mass * speed2KE - 1/2 mv2
Bouncing Ball Activity
Why can't the ball bounce back to it's original height?
ball transfers energy to the surface (absorbed)
some energy is transferred to sound
friction causes heat energy between the ball and the surface
Law of Conservation of Energy
Energy can be changed from one form to another or transferred.
If item X has a mass in grams of 100 and a volume in a ml of 50, what is its density?
d = m/v
100g/50mL = 2
Will item X sink?
Yes, because it is more dense than water
Why is easier to swim in the ocean than in fresh water or lakes?
Salt water is more dense than fresh water so it has a greater buoyant force making it easier to float.
What was the purpose of the carbon dioxide in the Dancing Raisins activity?
to change the density of the raisins
What unit would be used to measure the temperature of Mammoth Hot Springs in Yellowstone National Park?
Celsius
How many milliliters are in a liter?
1,000
_______ models are expressed in words and mathematics.
Conceptual
Sorting things into 2 mutually exclusive groups is referred to as _______ sorting.
dichotomous
Copernicus proposed a model of the universe where the sun was in the center and all other planets moved around it. This model is called the _________ model.
heliocentric
Which of the following is the correct order for the taxonomic hierarchy system?
kingdom, phylum, class, order, family, genus, species
We teach our student to sort and classify objects so they will become proficient in _________.
organizational skills
Two blocks are on a table. Block A has a volume of 30.0 cm3 and a mass of 81 g. Block B has a volume of 50.0 cm3 and a mass of 135 g. Which block has the greater density?
d=m/v
81 g/ 30 cm3 = 2.7
135 g/ 50 cm3 = 2.7
They are the same.
The meniscus in a graduated cylinder is read at the _______ of the curve.
bottom
An egg will float in salt water and sink in fresh water because . . .
The salt water's density is greater than the egg causing the egg to float.
5 m + 4 cm = _____ cm
504 cm
Which has more mass, a ton of feathers or a ton of iron?
neither - both have the same mass
In the activity where you found the mass and volume of several rods made of different materials, what did you conclude about the relationship between the density and mass?
the density increased as the mass increased
In the activity about the Cartesian diver, the eyedropper releases the extra water and floats back to the top when the pressure is . . .
released on the bottle.
Which of the following is NOT a measure of length?
kilometer
mile
liter
centimeter
liter
According to the diagram, how much fluid was displaced by the ball?
35 mL - 30 mL = 5 mL
According to Archimedes' principle, the buoyant force on the ball equals the weight of ______ mL of fluid.
5 mL
In the liquid density activity which liquid had the greatest density?
The one on the bottom
Which is larger?
25 cm
.26 m
200 mm
.0003 km
25 cm = .25 m
.26 m
200 mm = .2 m
.0003 km = .3 m
.0003 km
Which has less mass?
Regular Coke
Diet Coke
Same Mass for both
Diet Coke because less sugar and corn syrup
In the floating soap bubble activity, the reason that the bubble floated in the beaker is because ______?
The carbon dioxide's density is greater than the air and greater than the soap bubble.
The Earth's core is an example of a "black box". T or F
True
The activity about the Cartesian Diver demonstrated centripetal force? T or F
False
Objects with densities less than 1 g/cm3 float. T or F
True
Hot air is less dense than cool air. T or F
True
If an object floats, the buoyant force counters gravity. T or F
True
Boats float higher on salty seawater than fresh water because it is denser. T or F
True
111 cm = 1.11 m
T or F
True
Salinity affects density. T or F
True
In the "smokestack jar" activity, we learned that cold water is less dense than hot water. T or F
False
Cold water is more dense than hot water
After a rain if you look at puddles on the road you will often see a thin layer of oil floating on the water. This is because the density of the oil is greater than the density of water. T or F
