Answer: Physical
Explanation: There are no changes being done to the salt. Think of it this way, if you dissolve the salt in water then boil the water completely, you will have the same salt you started with.
According to the conservation of mechanical energy, the kinetic energy just before the ball strikes the ground is equal to the potential energy just before it fell.
Therefore, we can say KE = PE
We know that PE = m·g·h
Which means KE = m·g·h
We can solve for h:
h = KE / m·g
= 20 / (0.15 · 9.8)
= 13.6m
The correct answer is: the ball has fallen from a height of 13.6m.
Answer:
An asteroid is a minor planet of the inner Solar System. Historically, these terms have been applied to any astronomical object orbiting the Sun.
Answer:
It is possible to statically charge objects by rubbing it against carpet fibers, but I'm not sure if that was in the article that you read.
Explanation:
Static charge can build up via carpet fibers.
Answer: 14 m/s
Explanation:
The speed 
of a sound wave is given by the following equation:
Where:
is the wavelength of the sound wave
Hence:
