That particular group of elements is reffered to as the "Noble Gasses"--a title that comes from the fact that these gases are very "secure" and don't mix well with other elements.
Answer:10m/s
Explanation:
Wave speed ,v=for
Where π= wavelength=2m
Period =1/f f=frequency of wave
F=1/period
=1/0.2=5Hz
So speed of waves,v=5×2=10m/s
Answer:
acceleration, a = 9.8 m/s²
Explanation:
'A ball is dropped from the top of a building' indicates that the initial velocity of the ball is zero.
u = 0 m/s
After 2 seconds, velocity of the ball is 19.6 m/s.
t = 2s, v = 19.6 m/s
Using
v = u + at
19.6 = 0 + 2a
a = 9.8 m/s²
Is this practically possible? How can a 100kg man fly? Hahaha