Contact Forces
A force that happens when objects are physically touching
Contact Forces
Sound is produced by this:
Vibrations
A force that works from a distance
Non Contact Forces
The shape of earths orbit around the sun
Elliptical
The process where organisms better suited survive and reproduce
Natural Selection
A student pushes a box across the floor, but it eventually slows down and stops. What force is causing this?
Frtiction
A student plucks a guitar string and hears a sound. What caused the sound to start?
A: What are vibrations?
Vibrations
A paperclip moves toward a magnet without touching it. What type of force is acting on the paperclip?
Magnetic Force
During winter, one part of Earth receives less direct sunlight and has shorter days. What causes this?
Earths tilt (23.5 degrees)
A trait that helps an organism live
Adaptation
Two students push a desk from opposite sides with equal force, and it does not move. What is happening to the forces?
They are balanced or equal
A student notices that a louder sound makes a bigger movement in a speaker. What wave property is increasing?
Amplitude
The Moon stays in orbit around Earth instead of flying away into space. What force is responsible?
Gravity
The phase of the moon when over 75 percent of it is lit up
Gibbous
Some rabbits are faster than others. Predators catch the slower rabbits more often. Over time, the population becomes faster. What explains this change?
Natural Selection
A student pushes a book across a table. When they push harder, the book speeds up more quickly. What relationship between force and motion does this demonstrate?
Increasing force increases acceleration
A student hits a drum softly and then hits it harder. The second sound is louder. What changed about the sound wave?
Amplitude increased
What happens to gravitational force when mass increases?
It also increases
The Moon moves between the Earth and the Sun, blocking sunlight. What event is occurring?
Solar Eclipse
Why do populations change over time?
Variation and survival of the fittest (natural selection)
A heavier cart and a lighter cart are pushed with the same force. The lighter cart speeds up more. Why?
Less mass = greater acceleration or speed
How do sound waves travel through particles?
Vibrations passing from one particle to the next ( looks like the particles are vibrating)
Two objects are moved farther apart, and the force between them becomes weaker. What is happening to the force?
Force decreases with distance
What moon phase always starts the lunar cycle?
New moon (completely dark)
Fossils show that ancient species are similar to modern organisms but not identical. What does this suggest?
Common ancestry and evolution over time