4. Energy transfer is:
a. The movement of energy from one object to another.
b. Inherent in all objects.
c. Static in solids.
5. Insulators are:
a. Substances that transfer heat energy easily.
b. Substances that do not transfer heat energy easily.
c. All substances.
6. Convection is:
a. The way that heat energy flows through liquids and gases.
b. Transfer of heat energy by electromagnetic waves.
c. A space where there is no matter.
7. Radiation is:
a. Energy striking a surface and disappearing.
b. Energy which is absorbed by an object.
c. The transfer of heat energy by electromagnetic waves.
8. A dynamo is:
a. Fan-like machines that turn to produce mechanical energy.
b. Small generator that transfers mechanical energy into electrical energy.
c. A machine in a power plant that converts mechanical energy to electrical energy.
9. In an energy efficient system:
a. The energy produced must equal the energy which is needed.
b. No energy must be lost.
c. The energy gained must be greater than the energy lost.
10. Conduction is:
a. The transfer of heat between liquids that are in direct physical contact with each other.
b. The transfer of heat between solid objects that are not in direct physical contact with each other.
c. The transfer of heat between solid objects that are in direct physical contact with each other.
Answer (1)
Let's go through each of the questions one by one, providing detailed explanations for each:
Energy transfer is:
a. The movement of energy from one object to another.
This is the correct answer. Energy transfer refers to the movement of energy from one place or object to another. This can occur through various methods such as conduction, convection, and radiation.
Insulators are:
b. Substances that do not transfer heat energy easily.
This is the correct definition of insulators. Insulators are materials that resist the flow of heat or electricity, meaning they do not transfer these types of energy easily. Common examples include rubber, plastic, and glass.
Convection is:
a. The way that heat energy flows through liquids and gases.
Convection is the correct choice here. It is the process where heat is transferred through fluids (liquids and gases) by the movement of the fluid itself. Warmer, less dense regions of the fluid rise, while cooler, denser regions sink, creating a circulation pattern that transfers heat.
Radiation is:
c. The transfer of heat energy by electromagnetic waves.
This is the correct description of radiation. Radiation is the transfer of energy through space by electromagnetic waves, such as the heat from the sun reaching the Earth.
A dynamo is:
b. Small generator that transfers mechanical energy into electrical energy.
A dynamo is a device that converts mechanical energy into electrical energy, typically using a rotating coil of wire in a magnetic field.
In an energy efficient system:
b. No energy must be lost.
An ideal energy-efficient system aims to minimize energy loss and make the best use of the energy input. This helps to conserve resources and reduce waste.
Conduction is:
c. The transfer of heat between solid objects that are in direct physical contact with each other.
Conduction is the process where heat is transferred through direct contact between materials. It occurs when particles of matter collide, transferring energy directly to adjacent particles.
