Noble gases are not highly reactive
Answer:
a) A=0.125 m
b) T = 1.72 s
c) f= 0.58 Hz
Explanation:
a) As we are told that the maximum displacement from the equilibrium position was 0.125 m (from which it was released at zero initial speed), this is the amplitude of the resultant SHM, so, A=0.125 m
b) In order to find the period, we must get the total time needed to complete a full cycle (which means that the block must pass twice through the equilibrium point). We are told that at t=0.860 sec, the block has reached to the other end of the trajectory, and it has passed through the equilibrium point only once.
This means that the period must be exactly the double of this time:
T = 2*0. 860 sec = 1.72 sec.
c) In a SHM, the frequency is defined just as the inverse of the period (like in a uniform circular movement), so we can get the frequency f as follows:
f = 1/T = 1/ 1.72 s= 0.58 Hz
Answer:
2.80321285141
Explanation:
= Thickness of glass = 4.5 mm
= Thermal conductivity of glass = 0.8 W/mK
= Combined thermal resistance = 
= Thickness of air = 6.6 mm
= Thermal conductivity of air = 0.024 W/mK
The required ratio is the inverse of total thermal resistance

The ratio is 2.80321285141
Answer:
U₁ = 129.4 J
Explanation:
The potential energy is
U = mg y - m g y₀
Where I correspond to the initial position, with this it is an additive constant, we can make it zero with the placement of the reference system, in this case the system is placed on the floor where the ladder rests.
The power power for people on the floor is
U₀ = 0 J
The potential energy for the person on the first step is
U₁ = m g y₁
In general the steps are 20 cm high
y₁ = 20 cm (1m / 100cm) = 0.20 m
U₁ = 66 9.8 0.20
U₁ = 129.4 J