2nd 9 weeks Blog#5

Solar (energy derived from the sun) panels make sense as a primary means of obtaining usable energy when the 2nd law of thermodynamics ( Heat spontaneously flows from a substance of higher temperature to a substance of lower temperature and never spontaneously in the reverse direction & Any reaction is never 100% efficient, some energy is always lost as heat) is taken into consideration, because they are a renewable source of energy ( a source that is not going to be depleted). The solar panels will always take in energy from the sun during the day and are effective with energy saving.

1. Which type of energy can be converted with this device?
 
A. Oil
B. Nuclear
C. Solar*

2. When at the top of a roller coaster not moving which of the following would be the greatest?
A. Speed
B. Kinetic Energy
C. Potential Energy*

3. When an object is at equilibrium it is?
A. Accelerating
B. Slowing down
C. Being still/ Moving at a constant speed*

2nd 9 weeks blog #4

When you are riding on a roller coaster there are several instances were energy ( the capacity of a physical system to perform work) transformations occur. To begin with you start out on the ground, not moving with any potential energy ( the amount of energy potentially available due to gravity) and no kinetic energy ( the type of energy used when something is in motion). Then you are moving up slowly with low kinetic and growing potential. At the top potential energy is the greatest and kinetic is close to zero. On the way back down the potential energy continuously decreases while kinetic grows.
1. Potential energy is directly related to
     A. Speed
     B. Temperature
     C. Gravity/Height*
2 Potential energy transforms into kinetic energy when
     A. Mass Changes
     B. Temperature changes
     C. Speed/Motion changes*
3 A 5kg ball moving at 6m/s has a kenetic energy of _____
   A. 87
   B. 67
   C. 90j*

Energy

Nuclear Power, is the splitting of atoms creating a reaction which is used to heat water and create steam, I feel it is a useful energy source.
Hydrogen Fuel, fuel that is dependent upon hydrogen cells alone, it seems to be a green and efficient power.
Coal, a fossil fuel that is burned to release it's energy, dirty but effective.
Oil, a fossil fuel that runs the world, its energy is released by burning it, is bad for the environment and wasteful.
Living Green, is the practice of reducing your carbon footprint on the world.
Energy efficiency, is using every bit of energy to the fullest extent.
 1.What type of energy is produced here?

A. Nuclear*

B. Solar

C. Geothermal

2. What Unit is Energy Meaured in?

A. m/s^2

B. s

C. j *

3. A man pushes a 16000 car 22 m, what is his work?

A. 22j

B. 545 j

C. 352000 j