The answer should be B. A half step
Answer
given,
I is the loudness of sound
I = 10 Log₁₀ r
r is relative intensity
at when relative intensity is 10⁶
I = 60 dB
how much louder when 100 people would be talking together
I = 10 Log₁₀ r
I = 10 Log₁₀ (10⁶ x 100)
I = 10 Log₁₀ (10⁸)
I = 80 dB
hence, the intensity will be increased by (80 dB -60 dB) 20 dB when 100 people start talking together.
That's good ! I never heard of that before. (Maybe because
I've never been stung by an ant.)
When an ant bites or stings, it injects a tiny amount of 'formic acid'
into your skin. Soon, the formic acid itches, burns, and stings, and
after a while, a little piece of skin dies and falls off. Some people
are seriously allergic to it, and it can make them really sick.
'Acids' and 'bases' are opposites, and one can neutralize (cancel out)
the other. Tony is putting a weak 'base' on the sting, to neutralize the
formic acid that the ant left him as a little gift.
This problem here is an example of inelastic collision where kinetic energy is not conserved but momentum is. We calculate as follows:
m1v1 + m2v2 = (m1 + m2)v3
v3 = m1v1 + m2v2 / m1 + m2
v3 = (30.2)(1000) + (5000)(0) / (30.2 + 5000)
v3 = 6.00 m/s
An eraser, a type of rubber, uses static friction when rubbed across a sheet of paper.