Energy transformation

The blades of a toy helicopter spin when its circuit is connected to a battery. Which sequence below correctly identifies the energy changes taking place in the helicopter?

• chemical to electrical to potential

• chemical to electrical to mechanical

Tags

NGSS.HS-PS3-3

If 200 J of energy were added to 1 g each of aluminum and copper, which would experience the LEAST temperature increase. Refer to the formula below:

 $Q\ =\ mc\Delta T\ \ \ \ \ \ c\ =\ specific\ heat\ capacity$  

• Aluminum (c = 0.9 J/g C), because the higher the value for specific heat, the more energy is required for temperature change.

• Copper (c = 0.39 J/g C), because the lower the value for specific heat, the more energy is required for temperature change.

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

1. A hot (100 °C) bolt with a mass of 71 grams is placed in 150 grams of cool (20 °C) water.

This diagram shows the resulting temperature changes. The specific heat of water is 4.184 J/g × °C.

Approximately how many joules of heat did the water absorb?

(Heat Lost or Gained = Mass × Specific Heat × Change in Temperature) (Q = m c ΔT)

• 2,510.40 J

• 1,118.26 J

• 1,506.24 J

• 22,191.94 J

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

Which of the following gadgets best shows the transformation of energy from electrical to mechanical with the correct reasoning?

• A light bulb because electricity is being used to create light and heat.

• A fan because electricity is being used to spin the blades of the fan.

Tags

NGSS.HS-PS3-3

Two students place three ice cubes in a glass of water that was at room temperature. Which of the following scenarios would best describe the results of the investigation?

• Energy from the water will transfer to the ice cubes, causing the ice to melt.

• Cold from the ice cubes will transfer to the water, causing the water to cool.

Tags

NGSS.HS-PS3-4

A student decides to take up diving as a hobby. He stands on a high-dive that is 4m tall. If the student has a mass of 50 kg, what is his PE? Use the following equation to solve:

 $PE\ =\ mgh$  g = 9.8 m/s/s

• 1960 J

• 200 J

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-2

1. A student investigated the energy transformations that occur when a call is placed from cell phone A and received by cell phone B. The student drew a diagram to show the process. Based on the diagram, what evidence is there for the transformation of chemical energy into electrical energy, and which other energy transformations must occur for the call to be received by cell phone B?

• Evidence:

  Cell phones are powered by a battery that produces the electricity used to send or receive a call.

  Transformation 1: Sound energy is transformed into

  electrical energy by cell phone A.

  Transformation 2: Electrical energy is transformed into mechanical energy in the cell towers and base station

• Evidence:

  Cell phones are powered by a battery that produces the electricity used to send or receive a call.

  Transformation 1: Sound energy is transformed into

  electromagnetic waves by cell phone A.

  Transformation 2: Electromagnetic waves are transformed back into sound energy by cell phone B.

• Evidence:

  Base stations are powered by a battery that produces the electricity used to receive and forward a call.

  Transformation 1: Sound energy is transformed into electrical energy by cell phone A.

  Transformation 2: Electrical energy is transformed into mechanical energy in the cell towers and base station

• Evidence:

  Base stations are powered by a battery that produces the electricity used to receive and forward a call.

  Transformation 1: Sound energy is transformed into electromagnetic waves by cell phone A.

  Transformation 2: Electromagnetic waves are transformed back into sound energy by cell phone B

Tags

NGSS.HS-PS4-3

NGSS.HS-PS4-5

Choose the image below that shows potential energy decreasing then increasing if following the arrows from left to right?

• 
• 

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-2

1. Using the image identify the three forms of heat transfer.

Conduction (CD), Convection (CV) Radiation (R).

• A: CD - B: CV - C: R

• A: R - B: CD - C: CV

• A: CV - B: CD - C: R

• A: R - B: CV - C: CD

Tags

NGSS.HS-PS3-4

Choose the statement below that best describes the transfer of energy from the Sun to the Earth.

• The sun is the ultimate source of energy because it uses nuclear fusion to create heat. The thermal energy it creates radiates through the vacuum of space and heats the Earth.

• The Sun is an extremely large source of thermal energy. Because of its size, the Sun can conduct its heat through space, heating the Earth.

Tags

NGSS.HS-ESS1-1