Energy GoFar

Which of the following could be used to convert light energy to electrical energy? 

• a windmill
• a chemical storage battery
• a solar cell
• rotating coils in a magnetic field

In order to raise a box 3 meters to the awaiting bed of a tractor-trailer, you push it up a 10 meter ramp. The box is filled with books and weighs (W) 200 Newtons. You use a force (F) of 75 N applied parallel to the ramp.
Determine the amount of work you do against gravity.

• 225 J
• 750 J
• 600 J
• 2000 J

In a restaurant kitchen, lamps are used to keep food warm. Which type of electromagnetic radiation do the lamps emit that is primarily responsible for keeping the food warm?

• gamma
• ultraviolet
• infrared
• visible

Albert stirs a mug of hot chocolate with a metal spoon. What type of heat transfer is responsible for the spoon getting hot? 

• conduction
• convection
• thermoelectric
• radiation

Many restaurants and kitchens use iron skillets to cook bacon, eggs, and biscuits for breakfast. A standard skillet has a mass of 850 g. When cooking bacon for breakfast the skillet starts at a temperature of 25 degrees Celsius. At the end of cooking, the temperature of the skillet reaches 120 degrees Celsius. The specific heat of iron is 0.45 J/(g°C).

Determine the heat energy gained by the iron skillet.

• 4.03 J 
• 382.5 J
• 36,377.5 J
• 179,444.4 J

An inclined plane is used to move a heavy box from the ground into the bed of a truck. If 100 N of force is required to move the load up the ramp, how much work is done?   Disregard any force of friction. 

• 100 J
• 300 J
• 400 J
• 500 J

All of the following have what in common?  
-A light wave emitted from a bulb.
  -A radio wave picked up by your car stereo.
  -An ocean wave carrying a surfer to the beach.
  -An earthquake (wave) leveling homes on the west coast.

• They all transfer energy
• They all have equal wavelength
• They all travel at the same speed
• They all need a medium to travel through

In this type of heat transfer, no molecular motion is necessary. Heat can be transferred across large distances without any particles being present.

• Conduction
• Convection
• Radiation
• Transformation

Click picture to enlarge. Assuming all graphs are to the same scale, which of the electromagnetic waves has the GREATEST energy?         

• A
• B
• C
• D

Anne-Marie is using a fixed pulley to raise a weight. How does using the pulley change her effort?

• It reduces the effort needed to raise the weight 
• It changes the direction of the effort but doesn't reduce it
• It increases the effort needed to raise the weight
• It both reduces and changes the direction of the effort