Bubbles came off from the copper pennies are hydrogen gas. There many free hydrogen ions in an acid like vinegar. And because of the chemical reaction between the copper and the vinegar, many hydrogen ions joined together to form hydrogen gas.
-- Heat is a form of energy.
-- Joule is the SI unit of energy.
ergo
-- Joule is a unit of heat.
'Degree Celsius' and 'Kelvin' are units of temperature.
Heat and temperature are different things.
We won't go there right now.
Answer:
A. Their same forces repel each other, and their opposite forces attract each other.
Explanation:
As we know by the property of electric charge that similar charges repel each other and opposite charges attracts each other
So here we have similar situation in magnets also
Two similar poles or like poles of magnet i.e. North - North poles or South - South poles always repel each other
And also we can see that opposite poles of magnet each other i.e. North pole and south pole always attract each other.
SO here correct answer is
A. Their same forces repel each other, and their opposite forces attract each other.
Answer:
a) Ws = 2.548 J
b) Wf = 1.153 J
c) v = 1.923 m / s
Explanation:
a) The work done by the spring force
Ws = ½ * k * x²
Ws = ½ * 260 N/m *0.14² m
Ws = 2.548J
b) The increase in thermal energy can by find using
Et = Wf
Wf = µ * m *g * x
Wf = 0.42 * 2.0 kg *9.8 m/s² * 0.14m
Wf = 1.153 J
c) The speed just as the block reaches can by fin using
EK = Ws + Et
Ek = ( 2.548 + 1.153 ) J = 3.7 J
Ek = ½ * m * v²
v² = 2* Ek / m
v = √[2 * 3.7 J / 2.0 kg]
v = 1.923 m / s
