Systems
This is what we call a group of parts that work together to perform a function.
What is a system?
A ramp is an example of this type of simple machine.
What is an inclined plane?
This force pulls objects toward the Earth’s center.
What is gravity?
Energy is usually lost from a system through these three forms.
What are sound, heat, and friction?
This equation is used to calculate work.
What is work = force (N) x distance (m)
This is what a health care system is
What is a social system
This is the force the lever applied to the load
What is output force
The force that resists motion between two surfaces in contact is called this.
What is friction?
These devices in homes help prevent energy loss by automatically turning lights off when no one is in the room.
What are motion sensors/light sensors?
This equation is used to calculate mechanical efficiency.
What is (output work ÷ input work) × 100%?
A beehive, a forest, and the human body are all examples of this type of system.
What is a natural system
A flagpole uses this simple machine to raise and lower the flag.
What is a pulley?
The metric unit used to measure force is named after this scientist.
What is a Newton?
A light bulb “loses” energy because some electrical energy changes into this form instead of light.
What is heat/thermal energy?
A force of 10 N moves a box 3 m. How much work is done?
What is 30 J (joules)
A blow dryer takes in electrical energy and releases hot air. In this case, the hot air is the system’s
What is output?
This is where the fulcrum is in a first-class lever
What is between the input and the output
This property of matter never changes, no matter where you are in the universe
What is mass
An Energy Watchdog might recommend replacing old light bulbs with these, because they use less energy and waste less heat.
What are LED bulbs?
A student uses 50 N of force to push a box 4 m. The box only produces 150 J of useful output work. What is the efficiency of the system?
What is 75%
A bicycle is a system made up of smaller parts. The gear system, brake system, and wheel system are examples of these smaller working parts within the larger system.
What are subsystems?
A wheelbarrow is an example of this class of lever, where the load is in the middle.
What is a second-class lever?
What is the weight of gravity on earth?
What is 9.8 N/kg
When a toaster heats bread, electrical energy becomes heat. This is an example of energy being ________. When the hot toast warms your hand, that’s energy being ________.
What is transformed (electrical → thermal) and transferred (toast → hand)?
A pulley system requires an input force of 100 N over 2 m of rope pulled. The output force lifts a 100 N load 1 m. Calculate the efficiency.
What is 50%