Answer:
A) would be the best explanation because hot air is less dense and would rise to the top of a column of air
Somewhere in your book or your notes, you must have met the formula for the
gravitational attraction between two bodies. If you can go back and find it, you
only need to plug your numbers into that formula, and out will pop the answer.
Formula: <u>Force = G (mA x mB) / (distance)²</u>
If everything is in SI units, then G = 6.67 x10⁻¹¹ newton-meter² / kilogram²
You said that
mA = 8.1 kg
mB = 6.5 kg
distance = 0.5 m .
Force = (6.67 x 10⁻¹¹ nt-m²/kg²) (8.1kg x 6.5kg / (0.5m)² =
(6.67 x 10⁻¹¹ nt-m²/kg²) ( 52.65 kg² ) / (0.25 m²) =
<em>1.4047 x 10⁻⁸ newtons .</em>
That's roughly 5.052 x 10⁻⁸ ounce . (5% of one micro-ounce)
Answer:
(a) 
(b) 
Explanation:
According to the law of conservation of momentum:

Initially, the girl and the plank are at rest. So, relative to the ice, we have:

(a) The velocity of the girl relative to the ice is:

Here,
is the velocity of the girl relative to the plank and
is the velocity of the plank relative to the ice.
Replacing (1) in (2):

(b) According to (2), the velocity of the plank relative to the surface of ice is:

The negative sing indicates that the plank is moving to the left.
Not sure of what answers you are given, but what I can think of is a transverse wave.
Answer:
C ) 33 s.
Explanation:
In simple harmonic motion damping of amplitude is logarithmic which is expressed as follows

A/A₀ = .3 (given ) , b is damping constant and t is time which is 30 s here.

ln .3 = -b / 30
1.2 = b / 30
b = 36 s 0r 33 s