Forces
What is Newton's Third Law of Motion?
For every action force, there is an equal and opposite reaction force.
When a predator eats its prey, is the energy transfered or transformed? Explain.
Energy is transfered as the chemical energy just moves from the prey to the predator (changes location) (but at 10%)
chemical energy --> chemical energy
What type of mixture is formed when one substance disolves into another substance?
What chemical changes occur when vinegar is added to baking soda?
Production of Gas in the form of bubbles
Temperature change (it gets colder)
Give an example of a senario when chemical energy would change into kinetic energy.
answers may vary.
Describe what happens with two south poles of a magnet are placed close together. What happens when a north and south pole of a magnet are placed close together?
The two south poles will repel and the north and south will attract. *Opposites attract, like repel.
Decribe the energy transformation that occurs in a flashlight
chemical energy--> eletrical --> light (and thermal)
What is the main difference betwen pure substanes and mixtures?
Mixtures can be physically separated (more than one pure substance combined), pure substances cannot be physically separated.
A blue liquid is mixed with a yellow liquid to make a green liquid. Is this a physical or chemical change?
physical change
What is the difference between a balanced and an unbalanced force?
A balanced force is either at rest (stationary) or moving at constant speed (like the earth as it rotates). An unblanced forces causes an object to speed up, slow down, stop, or change directions.
A boy is on a small boat in a pond. He pushes a floating cooler away from him to the east. Which direction will the boat move? Which law explains why this happens?
the boat will move to the west (opposite direction)
The law of action reaction (Newton's 3rd Law) will cause the boat to mvoe in the opposite direction. (equal and opposite reaction)
Which energy transformation occurs when a mouse runs away from a cat?
The chemical energy in the mouse is converted to kinetic energy (runs).
Ocean water is an example of which type of mixture?
Homogeneous Mixture because it is a solution of water and salt and looks the same throughout.
What is the difference between mass and volume? What can you use to measure each?
Mass measure the amount of matter in an object and can be measure using a triple-beam balance or scale. Volume measures the amount of space an object takes up and can be measured using a beaker, or a retangular prism can me measured by length x width x height.
What would cause magnets to repel?
Place two north poles or two south poles together (likes repel)
A boy pushes cart with a mass of 16 kg with a force of 25 N to the left on a surface with a frictional force of 7N. What is the net force?
The cart will move to the left with a force of 18N.
Describe the energy transformation that occurs when a plant is placed outside.
The light/radiant energy from the sun is converted to chemical energy in the plant.
What is the difference between an element and a compound?
Both are pure substances. An element is made of only one type of atom and a compound is made of more than one type of atom chemically combined.
How can you know if a chemical reaction takes place? (HUGS)
H-heat/temperature changed when mixed (change in temperature not due to directly heating up or cooling down)
U-unexpected color change (ie blue and yellow turn purple, two clear liquids turn white)
G-gas formation (gas formed that was not already there)
S-Solid precipitate formed when two liquids are combined.
Explain why a ball will slow down as it moves across a field of grass.
There is an unbalanced (slows down) force on the ball caused by friction.
Describe two forces acting on a soccer ball during a soccer game and their effect on the motion of the ball.
An applied force is used to kick the ball which causes it to speed up or change directions. A fricitonal force acts between the ball and the grass causing it to slow down. When the ball is in the air, gravitiy pulls it back down to the ground.
Determine which type of potential or kinetic energy is demonstrated in each of the senarios below:
1. A car is parked at the top of a hill.
2. A ball rolls across the field.
3. The food is on the plate.
4. A girl gets ready to jump off of a trampoline onto the floor.
1. gravitational potential energy
2. kinetic energy
3. chemical energy
4. elastic potential energy (from springs on trampoline) and gravitational potential energy (due to height)
What is the difference between a homogeneous and a heterogeneous mixture? Give an example of each.
A homogeneous mixture is the same/uniform throughout (Ex: Solution of salt and water, kool-aid), Heterogeneous mixtures are different thoughout (ex: trail mix, sand and water, sand and iron filings)
What is the difference between malleability and ductility?
Malleable means it can bend without breaking and ductile refers to being able to stretch into a wire. Both are physical properties of metals.
35 N to the east.