Answer:
A. independent variable.
Explanation:
In this experiment, the types of box materials are a(n) independent variable, which is when you purposely change things or control them, hoping for a specific outcome.
No voltage, no current. The battery provides potential difference(v) to the circuit. In case of no potential difference, theres no current.
Here is the link with ans on it
https://moorsscience.wikispaces.com/file/view/chapter+12+answers.pdf
hope it helps
Answer:
1. heat engine ~~ •a machine that converts the internal energy of a fuel into mechanical energy.
2. heat pump ~~ •an appliance that extracts heat energy from one source and deposits it
elsewhere.
3. Boiler ~~ •a heating appliance that uses heat energy released from fossil fuels to warm water for use in radiant or
convection heating systems.
4. Thermostat ~~ •an appliance that controls the maintenance temperature of a heating
system
