People use oven mitts to avoid getting burns when moving hot metal pans while cooking.
Which physical property of the metal pan requires the use of an oven mitt when it is hot?
(1 point)
O Low thermal conductivity
O Low magnetism
O High solubility
• High thermal conductivity
• High thermal conductivity
Convection ovens cook food more evenly than a standard thermal oven. Which statement explains how a convection oven works? (1 point)
O Hot air is transferred through direct molecule contact.
• Hot air is transferred through density differences when hot air rises and cool air sinks.
• Hot air is transferred when heat radiates from a thermal burner.
• Hot air is transferred through density differences when cool air rises and hot air sinks.
• Hot air is transferred through density differences when hot air rises and cool air sinks.
Which investigation would best show the transfer of heat energy without any type of matter as a medium? (1 point)
O an investigation of conduction through movement of particles within a solid
an investigation of conduction using collisions between particles
O an investigation of radiation using electromagnetic waves
• an investigation of radiation using a current within a fluid
• an investigation of radiation using electromagnetic waves
An aluminum block has a starting temperature of 300C. The block is placed into 200 milliliters of water, which has a temperature of 20oC. What heat transfer will occur? (1 point)
• Heat will flow from the block to the water until both have a temperature of 300oC.
• Heat will flow from the block to the water until both substances have the same temperature as their container.
Heat will flow from the block to the water until both substances have a temperature between 20 degrees
О
Celsius and 300 degrees Celcius.
• Heat will flow from the block to the water until both substances have a temperature of 20 degrees Celcius.
• Heat will flow from the block to the water until both substances have the same temperature as their container.
17. Two samples of pure water are mixed with food coloring. One sample is red, and the other is blue.
When the two water samples are combined, the red water floats on top of the blue water. Which statement best explains this result? (1 point)
• The red water is colder and is more dense.
O The red water is warmer and is less dense.
• The blue water is, colder and is less dense.
• The blue water is warmer and is more dense.
• The red water is warmer and is less dense.
Betsy uses an electric alarm clock to wake up for school. What energy transformation happens in the alarm clock to help her wake up? (1 point)
O electrical energy converts to sound energy
• sound energy converts to kinetic energy
• electrical energy converts to heat energy
•chemical energy converts to electrical energy
O electrical energy converts to sound energy
As energy is transferred or conserved, some of that energy becomes unavailable to do work. What happens to this unavailable energy? (1 point)
• The unavailable energy is given off as microwaves
• The unavailable energy is given off as heat
• The unavailable energy is destroyed
• The unavailable energy is conducted
• The unavailable energy is given off as heat
Often Bobby sees his pinwheel spinning, but other times it does not spin. Which statement best explains what makes his pinwheel spin?
(1 point)
• Energy from the wind pushes on the wheel causing the pinwheel to move.
• The Sun heats up the pinwheel, causing it to turn.
• The colors on the wheel repel one another, causing it to turn.
• Energy from the ground shakes the wheel causing the pinwheel to move.
• Energy from the wind pushes on the wheel causing the pinwheel to move.
Kim is upstairs, but walks downstairs to the kitchen for a snack. Which statement correctly describes the types of energy she has at the top of the stairs and as she walks down the stairs? (1 point)
O potential energy at the top of the stairs; kinetic energy as she walks down
• kinetic energy at the top of the stairs; kinetic energy as she walks down
kinetic energy at the top of the stairs; potential energy as she walks down
• potential energy at the top of the stairs; potential energy as she walks down
O potential energy at the top of the stairs; kinetic energy as she walks down
Rebecca climbs the ladder of a large water slide, waits her turn at the top, and then slides down the slide into a pool. Which answer best describes the energy changes during her time on the slide? (1 point)
O kinetic - mechanical - potential
O potential - mechanical - kinetic
O kinetic - potential - kinetic
O potential - kinetic - potential
O potential - kinetic - potential
When an object is in motion, it possesses what type of energy? (1 point)
O chemical energy
• potential energy
• thermal energy
• kinetic energy
• kinetic energy
An object's gravitational potential energy depends on the object's mass, the strength of the gravitational field, and what other variable? (1 point)
• the color of the object
• the shape of the object
• the speed of the object
• the object's height from the ground