heat and expansivity

The transfer of thermal energy between objects of different temperatures is called...

• temperature
• heat 
• none of these

Tags

NGSS.MS-PS3-3

NGSS.MS-PS3-4

NGSS.MS-PS3-5

The faster an object moves, the ________ kinetic energy it has. 

• more
• less
• none of the above
• all of the above 

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-5

A jacket is a good example of an . . .

• Insulator
• Investigator
• Insider
• Interrogator

Tags

NGSS.MS-PS3-3

What is the BEST example of a conductor? 

• A wooden block
• A ceramic mug
• A glass cup
• A metal bowl

The heat from a lamp allows a lizard to remain warm. This is an example of which type of heat transfer?

• radiation
• conduction
• convection
• insulation

What is the definition of CONDUCTION?

• When heat is transferred from objects like rays of light or electromagnetically.
• a  hot liquid or air that  expands, becomes less dense, and rises or becomes more dense, and sinks.
• When heat transfers from objects that are touching.
• When heat transfers through the heater or AC in your house.

Tags

NGSS.MS-PS1-4

An iron rod of length 50 m and at a temperature of 60⁰C is heated to 70⁰C. Calculate its new length.

(Linear expansivity of iron = 1.2 x 10^-5 K^-1)

• 50.006 m

• 50.060 m

• 51.600 m

• 51.200 m

A brass rod is 2m long at a certain temperature. Calculate the linear expansion of the rod for a temperature change of 100 K. (Linear expansivity of brass = 1.8 x 10^-5 K^-1)

• 0.3600 m

• 0.1800 m

• 0.0360 m

• 0.0036 m

A metal rod of length 40.00 cm at 20⁰C is heated to a temperature of 45⁰C. If the new length of the rod is 40.05 cm, calculate its linear expansivity.

• 1.2 x 10^-5 K^-1

• 2.5 x 10^-5 K^-1

• 3.5 x 10^-5 K^-1

• 5.0 x 10^-5 K^-1

Steel bars, each of length 3.0 m at 28⁰C, are to be used for constructing a rail line. If the linear expansivity of steel is 1.0 x 10^-5 K^-1, what is the safety gap that must be left between successive bars if the highest temperature expected is 40⁰C ?

• 1.2 x 10^-1 cm

• 8.4 x 10^-2 cm

• 3.6 x 10^-2 cm

• 1.8 x 10^-2 cm