Answer: You do not specify what is being asked for. ∆E? ∆H?
∆E = (430 - 238) J = 192 J
∆H = 430 J
Explanation:
If asked for the value of ∆H the answer is simply the change in heat, and in the question, it states introduction of 430 J of heat is causing the system to expand.
Therefore ∆H = 430 J
If asked for ∆E, we know that ∆E = ±q (heat) + work (-P∆V) = ±q + w
The question states that 238 J of work are done AND the system expanded
(work is negative because expansion means work is done BY the system, releasing energy/heat... Conversely, if the system were compressed, work is done ON the system, absorbing heat/energy)
Therefore, ∆E = (430 - 238) J = 192 J
Here is the answer. Two sources of Earth's energy that are not produced would be Cosmic rays and Tidal Energy. Cosmic rays <span>are high-energy protons and atomic nuclei that come from outside the solar system. Whereas, tidal energy is the energy produced by both the moon (2/3) and the sun (1/3). Hope this answers your question.</span>
The buoyant force on any object acts in the direction opposite to the force of gravity. <em>(A)</em>
Answer:
<em>a) 0.72 V</em>
<em>b) 19.2 mA</em>
<em>c) 2.304 Watts</em>
Explanation:
A transformer is used to step-up or step-down voltage and current. It uses the principle of electromagnetic induction. When the primary coil is greater than the secondary coil, the it is a step-down transformer, and when the primary coil is less than the secondary coil, the it is a step-up transformer.
number of primary turns = 
= 500 turns
input voltage = 
= 120 V
number of secondary turns = 
= 3 turns
output voltage = 
= ?
using the equation for a transformer
substituting values, we have
= 360/500 =<em> 0.72 V</em>
<em></em>
b) by law of energy conservation,
where
= input current = ?
= output voltage = 3.2 A
= output voltage = 0.72 V
= input voltage = 120 V
substituting values, we have
120 = 3.2 x 0.72
120 = 2.304
= 2.304/120 = 0.0192 A
= <em>19.2 mA</em>
<em></em>
c) power input = 
==> 0.0192 x 120 = <em>2.304 Watts</em>
