If dirt and grease were good conductors of electrical current, then we could make wire
out of dirt and grease instead of expensive copper. Sadly, they're not. So a coating of
dirt and grease on the wire can have a substantial impact on the connection, and can
even block the flow of current across the connection completely. Moreover, in the case
where the ends of the wires are to be soldered, solder does not adhere to dirty wire.
Answer:
A. When it is in a magnetic field, it becomes a temporary magnet.
Explanation:
An iron bolt is attracted to a magnet because when in a magnetic field, the iron becomes a temporary magnet.
This is because the iron aligns their electrons in the magnetic fields.
- This causes that attraction between the magnet and the iron.
- Metals like iron are said to be ferromagnetic
- Unpaired electrons in iron spin in such a way that they align with the magnetic fields of the magnet.
Heat rises therefore the heat from the fire rises up to your hand... i didnt have any answer choices to work with sorry
Answer:
C) Use a battery with more voltage.
Explanation:
The equation for the magnetic field around a coil is given by,
B = μ₀NI
where,
B = Magnetic flux density
μ₀ = permeability
N = number of turns per meter
I = Current in the wire
So when using a higher voltage battery, more current passes through the battery as resistance of the wire remains the same.
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:
