Answer:
Explanation:
A white object reflects almost all of the visible light shone on it, black “absorbs” almost all of the visible light spectrum shown on it. The white object under the yellow light will reflect yellow light back to your eye, as will the yellow object.
Answer:Because cell phones and base stations use low-power transmitters, the same frequencies can be reused in non-adjacent cells.
Explanation:
Answer:
a) 0.002 cm³
b) 0.005 cm³
Explanation:
density d = 19 kg/cm³
Given mass m, find volume V
The definition of density is
d = m/V
so V = m/d
a) m = 38 g = 0.038 kg
so V = 0.038/19 = 0.002 cm³
b) m = 0.095 kg
V = 0.095/19 = 0.005 cm³
From the law of atmosphere
Where
= constant and is number density where the height y = 0cm
= Number density at height y=3cm
Kb = Boltzmann constant
Re-arranging the equation to have the value of the gravity,
Since it is 30% of value above surface, therefore
Therefore the correct answer is C.
Answer:
Explanation:
You have to declare which way is plus -- up or down. I will use down.
vi = - 2.85 The balloon is going up. That is the minus direction.
a = 9.81
d = 2.50 meters distance in this case is from the object to the ground.
d = vi*t + 1/2 a t^2
-2.50 = -2.85*t + 1/2 * 9.81 * t^2
-2.50 = -2.85*t + 4.905 * t^2 transfer the left to the right.
-4.905 t^2 + 2.85*t + 2.50 = 0
Use the quadratic formula to solve for t.
It turns out that t = 1.06