Science Study Guide – Chapter 11
Changing Motion
Velocity refers to the speed and direction of motion.
Frame of reference refers to position.
The distance traveled and time is the information that is needed in order
to calculate speed.
Study the diagram below:
Position
Ways to Describe
Motion
Velocity
Speed
If you rolled a ball across the ground on the Moon, how would it compare to
a ball rolled on Earth? The ball on the Moon would roll farther than the
ball on Earth because there is less gravity on the Moon. The ball
would also bounce much higher on the Moon, because the pull of
gravity is weak.
A newton is a unit that measures force.
When two children of equal weight sit at opposite ends of a seesaw, they
create balanced forces.
Color is the only thing that does not affect inertia.
Study the diagram below:
Cause
Bricks are loaded
into an empty
wheelbarrow
Effect
More force is
required to move the
wheelbarrow
A chef coats cooked spaghetti with oil before putting sauce on the spaghetti,
what force is the chef trying to control? The chef is trying to control
friction. The oil is slippery, so it decreases the friction between the
spaghetti noodles. If oil was not used, the spaghetti noodles would
stick together.
Work involves force, movement, and distance, but does NOT involve time.
Potential energy DOES NOT always involve gravity.
Energy that comes from the tiniest particles of matter is known as nuclear
energy.
Study the diagram below:
Cause
A ball rolls downhill
Effect
Kinetic energy is
created
Are you doing work when you blow a bubble with chewing gum? Yes, work
is the use of force to move an object. When you blow a bubble, your
breath is moving and stretching the chewing gum.
A playground seesaw is a type of lever.
The force used to do work best describes “effort force.”
A ceiling fan is an example of a wheel and axle.
Friction reduces the efficiency of a machine.
Imagine that you needed to roll a large boulder several feet. What simple
machine would you use to perform this task? A lever would be a good
simple machine to move a rock. One end of the lever could be
wedged under the rock, which would help to start it roll when effort
force was applied to the other end of the lever.