A student with a body temperature of 37°C holds a can of cold soda with a temperature of 18°C. The student is in a room with an air temperature of 22°C. Which statement best describes the flow of heat throughout the entire system?
Responses
Heat will flow from the air to the can and the student.
Heat will flow from the air to the can and the student.
Heat will flow from the student to the can and the air to the can.
Heat will flow from the student to the can and the air to the can.
Heat will flow from the student to the can.
Heat will flow from the student to the can.
Heat will flow from the student to the can and the air, and from the air to the can
Heat will flow from the student to the can and the air, and from the air to the can
The diagram shows a simple pendulum. Neglecting friction, what happens to the total mechanical energy as the pendulum swings from position A to position B?
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Responses
It decreases.
It decreases.
It increases.
It increases.
It remains the same.
It remains the same.
It is not conserved.
A is still while B is on the left side swinging
The total mechanical energy remains the same.
Leanna is investigating heat transfer using a metal nail and foam cup filled with hot water. First, she records the temperature of the water and nail. Next, she places the nail in the hot water for ten minutes. Finally, she removes the nail from the water and records the temperature of the water and nail. The table shows her data. How does the motion of the molecules in the nail change after the nail is placed in the hot water?
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Responses
Energy was transferred between the hot water and the nail through conduction, causing the molecules in the nail to move slower.
Energy was transferred between the hot water and the nail through conduction, causing the molecules in the nail to move slower.
Energy was transferred from the hot water to the nail through convection, causing the molecules in the nail to move faster.
Energy was transferred from the hot water to the nail through convection, causing the molecules in the nail to move faster.
Energy was transferred from the hot water to the nail through conduction, causing the molecules in the nail to move faster.
Energy was transferred from the hot water to the nail through conduction, causing the molecules in the nail to move faster.
Energy was transferred between the hot water and the nail through convection, causing the molecules in the nail to move slower.
Hot water temp
50C
Metal Nail temp
20C
AFTER 10 MINS
Hot water temp
35C
Metal Nail Temp
30C
Energy was transferred from the hot water to the nail through conduction, causing the molecules in the nail to move faster.
The diagram below shows two flasks of water, one with hot water and the other with room temperature water, which are connected by a conductive metal bar. When initially set up, in which direction does the thermal energy between the flasks flow?
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Responses
Thermal energy does not flow between the two flasks.
Thermal energy does not flow between the two flasks.
Thermal energy flows from the flask on the left to the flask on the right.
Thermal energy flows from the flask on the left to the flask on the right.
Thermal energy flows equally between the two flasks.
Thermal energy flows equally between the two flasks.
Thermal energy flows from the flask on the right to the flask on the left.
Thermal energy flows from the flask on the right to the flask on the left.
Thermal energy flows from the flask on the left to the flask on the right.
Which of the following is true as the cars of a rollercoaster race down a hill?
Responses
Kinetic energy is stored in the cars as they move downhill.
Kinetic energy is stored in the cars as they move downhill.
The kinetic energy of the cars is equal to the potential energy of the cars.
The kinetic energy of the cars is equal to the potential energy of the cars.
Some energy is destroyed as the cars slow down.
Some energy is destroyed as the cars slow down.
Some potential energy is transformed to kinetic energy and other forms of energy.
Some potential energy is transformed to kinetic energy and other forms of energy.
Heat will flow from the student to the can and the air, and from the air to the can.
To explain the answer, we need to understand the concept of heat transfer. Heat naturally flows from objects at higher temperatures to objects at lower temperatures until thermal equilibrium is reached.
In this scenario, the student has a body temperature of 37°C, which is higher than both the air temperature (22°C) and the temperature of the cold soda can (18°C). Therefore, heat will transfer from the student to the colder soda can and from the student to the air in the room.
Simultaneously, heat will also transfer from the warmer air in the room (22°C) to the colder soda can (18°C) to reach thermal equilibrium.
Hence, heat will flow from the student to the can and the air, and from the air to the can.