Answer: It's D
Explanation: just took the test
The answer is <span>Guardrails and protective equipment. </span><span>When hoisting a personnel platform, guardrails and protective equipment need not be engaged when they occupied platform is in a stationary position. </span>
Answer:
a) P=0.25x10^-7
b) R=B*N2*E
c) N=1.33x10^9 photons
Explanation:
a) the spontaneous emission rate is equal to:
1/tsp=1/3 ms
the stimulated emission rate is equal to:
pst=(N*C*o(v))/V
where
o(v)=((λ^2*A)/(8*π*u^2))g(v)
g(v)=2/(π*deltav)
o(v)=(λ^2)/(4*π*tp*deltav)
Replacing values:
o(v)=0.7^2/(4*π*3*50)=8.3x10^-19 cm^2
the probability is equal to:
P=(1000*3x10^10*8.3x10^-19)/(100)=0.25x10^-7
b) the rate of decay is equal to:
R=B*N2*E, where B is the Einstein´s coefficient and E is the energy system
c) the number of photons is equal to:
N=(1/tsp)*(V/C*o)
Replacing:
N=100/(3*3x10^10*8.3x10^-19)
N=1.33x10^9 photons
Answer:
FLASH FLOODS CAN CAUSE VEHICLES TO FLOAT AND FILL WITH WATER, TRAPPING AND DROWNING PEOPLE. WHILE ESPECIALLY DANGEROUS AT NIGHT AND IN DEEP WATER, EVEN ____ INCHES OF WATER CAN FLOAT SOME SMALL CARS.
The Answer is SIX Inches.
Explanation:
Flash floods: are short-term events and are associated with short, high-intensity rainfall which occur when creeks that are normally dry fill up and other creeks overflow. Densely populated areas have a high risk of flash floods. Water levels in flash floods can rise one foot in five minutes making Six inches of water able to reach the bottom of most passenger cars. Moving water will exert pressure on a car. The car floats downstream when stream force exceeds the friction force, the car will be carried when bouyancy force (which is the upward force exerted by any fluid upon a body placed in it) is greater than vehicle weight.
Answer:
The coefficient of static friction between the box and floor is, μ = 0.061
Explanation:
Given data,
The mass of the box, m = 50 kg
The force exerted by the person, F = 50 N
The time period of motion, t = 10 s
The frictional force acting on the box, f = 30 N
The normal force on the box, η = mg
= 50 x 9.8
= 490 N
The coefficient of friction,
μ = f/ η
= 30 / 490
= 0.061
Hence, the coefficient of static friction between the box and floor is, μ = 0.061
