Answer:
The correct answer is -0.129 kJ
Explanation:
In the given case, the cooling of the balloon is done by withdrawing 0.784 J of heat, and the work done by the atmosphere on the balloon is 655 J. First, there is a need to transform kJ into J, 1 kJ = 1000 J. So, 0.784 kJ would be 784 J.
The ΔE or the change in the internal energy can be calculated by using the formula, ΔE = q + w ----- (1).
In the given case, q refers to the heat moved out of the system, that is, the value of q would be less than 0 or will be a negative quantity. Therefore, the heat moved out of the system will be -784 J. On the other hand, as the work or w is done on the system, therefore, the value of w would be more than 0 or will be a positive quantity. Thus, the value of w will be +655 J.
Now putting the values in the equation (1) we get,
ΔE = -784 J + 655 J
ΔE = -129 J or -0.129 kJ
As the change in internal energy comes out to be a negative value, therefore, the process is considered exothermic.
A COMBUSTION reaction occur when a substance ...........................................
Combustion reaction is also known as burning. It occurs when an hydrocarbon react with oxygen to yield carbon dioxide, water and energy in the form of light and heat. Combustion reaction can not take place in the absence of oxygen.
Answer:
Galileo performed a famous experiment where he used a ball rolling on a ramp (inclined plane) to study the motion of objects under the influence of gravity. The ramp allowed him to make more precise measurements because the ball moved more slowly along the ramp than if it were simply dropped. Galileo discovered through this experiment that the objects fell with the same acceleration, proving his prediction true, while at the same time disproving Aristotle's theory of gravity (which states that objects fall at speed proportional to their mass). Galileo's conclusion from this thought experiment was that no force is needed to keep an object moving with constant velocity. Newton took this as his first law of motion. One result of the experiment surprised Galileo, and one surprises us. Galileo found that the heavy ball hit the ground first, but only by a little bit. Except for a small difference caused by air resistance, both balls reached nearly the same speed. And that surprised him. According to history, Galileo’s experiment on falling bodies largely contributed to Isaac Newton’s Law of Gravity. In Galileo’s experiment, he is said to have dropped balls from the Leaning Tower of Pisa. The balls were made of the same material but had different masses. Galileo set out to prove that the time it took for these objects to reach the ground would be the same. Galileo proved that objects reached the ground at the same time,
Explanation:
I think this is right & I hope this helped
The answer is Mg3 glad I helped
I would say that descriptive investigations aren't repeatable because it means that you are only describing something - you ask certain question about something, but do not form a hypothesis at that point yet. So it would be a waste of time to simply ask the same questions over and over again with no hypothesis to prove, which is why these types of investigations cannot be repeated.
