From the choices given, ultraviolet rays is a type electromagnetic radiation that causes certain substances to fluoresce. It cannot be detected by the naked eye but some insects are able to see them.
Like in a fluorescent light bulb, ultraviolet or UV lights stimulates the coating of the tube to emit light.
A change in the physical properties like mass or texture will not cause any change in the substance because the composition of the substance will retain the same.
<u>Explanation:</u>
A change of the physical properties will affect only the size, shape and structure of the compound, it won't be affecting the composition of the compound. Since any kind of change in the physical properties of the compound will only affect the outermost structure of the compound or the size of the compound.
It will not change the bond structure and neither it will break any bonds, thus the substance will be as it is. So, there will be no change in the substance on changing the physical properties like mass or texture, as the composition and bonding in the substance will retain the same.
Answer:
B = 0.07 mT
Explanation:
q = 1.6x10^-19 coulombs
for the electron to pass through the field undeflected the magnetic force acting on it must equal the electrical force due to the electric field
electric force = Eq = 16000 * 1.6x10^-19 newtons
magnetic force = qvB = 1.6x10^-19 * 2.7x10^8 * B
16000 * 1.6x10^-19 = 1.6x10^-19 * 2.7x10^8 * B
B = 0.07 mT (milli tesla)
