<span>So we need to put in the correct words to fill in the blanks. The FIRST law of thermodynamics states that energy can't be created or destroyed. It is a formulation of the law of conservation of energy modified for thermodynemical systems. Two natural sources of energy on Earth are the solar and wind. Also geothermal energy and hydropower are natural sources of energy. </span>
Answer:
Chemical energy to electrical energy
Explanation:
In nature, there are several types of energy.
In this example (a flashlight being turned on), we have a conversion of energy from chemical energy to electrical energy. In fact:
- Chemical energy is the energy stored in the chemical bonds of the molecules of the substances used inside the battery. When the chemical reaction inside the battery occurs, this energy is liberated, and it is used to "push" the electrons along the circuit connected to the battery
- Electric energy is the energy associated to the motion of the electrons along the circuit of the flashlight; it is the energy associated to an electric current.
Moreover, in the flashlight the electric energy is then converted into two more types of energy: light energy (since the bulb in the flashlight produces light) and heat energy (because the flashlight also produces heat, so thermal energy).
Answer:True
Explanation: The mechanical waves need a medium through which to transport energy because the perturbation travels inside of the medium so it needs molecules that connect elastically the displacement of the wave. For example the sound mainly uses the air molecules to transport the energy also the sound can be traveled in solid materials like metal rods.
Answer:
4.42 x 10⁷ W/m²
Explanation:
A = energy absorbed = 500 J
η = efficiency = 0.90
E = Total energy
Total energy is given as
E = A/η
E = 500/0.90
E = 555.55 J
t = time = 4.00 s
Power of the beam is given as
P = E /t
P = 555.55/4.00
P = 138.88 Watt
d = diameter of the circular spot = 2.00 mm = 2 x 10⁻³ m
Area of the circular spot is given as
A = (0.25) πd²
A = (0.25) (3.14) (2 x 10⁻³)²
A = 3.14 x 10⁻⁶ m²
Intensity of the beam is given as
I = P /A
I = 138.88 / (3.14 x 10⁻⁶)
I = 4.42 x 10⁷ W/m²
Answer:
a.
Explanation:
cuz whenever the ball was traveling up the staircase it was building up energy to use (potential energy) unlike b.
