Science 9 _HEAT

What is the best definition of heat?

• A measure of the total energy in a system

• The transfer of thermal energy between objects of different temperatures

• The total kinetic energy of molecules in an object

• A measure of how hot or cold an object is

Which of the following statements about temperature is true?

• Temperature is a form of energy

• Temperature measures the total energy of a system

• Temperature measures the average kinetic energy of particles

• Temperature is the same as heat

3. Internal energy includes which types of energy?

• Only kinetic energy

• Only potential energy

• Both kinetic and potential energy

• Neither kinetic nor potential energy

According to the First Law of Thermodynamics, which equation is correct?

• Q = W - ΔU

• Q = W + ΔU

• Q = ΔU - W

• Q = ΔU ÷ W

If 150 J of energy is added to a system and it does 50 J of work, what is the change in internal energy?

• 50 J

• 100 J

• 150 J

• 200 J

When does an object perform work?

• When it is in motion

• When a force is applied but does not cause movement

• When a force is applied, and the object moves in the direction of the force

• When heat is transferred from one object to another

What happens to the internal energy of water when it is heated?

• It decreases

• It remains the same

• It increases

• It turns into kinetic energy

Who is the scientist known for establishing the relationship between mechanical, electrical, and heat energy?

• Isaac Newton

• James Prescott Joule

• Albert Einstein

• Nikola Tesla

What unit is used to measure heat energy?

• Newton

• Joule

• Celsius

• Watt

Why does boiling water reach a maximum temperature of 100°C at standard pressure?

• Because temperature and heat are the same

• Because energy is no longer being added

• Because the added energy is used to change the state of water rather than increasing temperature

• Because the water loses energy