Answer:
C = 1.01
Explanation:
Given that,
Mass, m = 75 kg
The terminal velocity of the mass, 
Area of cross section, 
We need to find the drag coefficient. At terminal velocity, the weight is balanced by the drag on the object. So,
R = W
or
Where
is the density of air = 1.225 kg/m³
C is drag coefficient
So,
So, the drag coefficient is 1.01.
If it produces 20J of light energy in a second, then that 20J is the 10% of the supply that becomes useful output.
20 J/s = 10% of Supply
20 J/s = (0.1) x (Supply)
Divide each side by 0.1:
Supply = (20 J/s) / (0.1)
<em>Supply = 200 J/s </em>(200 watts)
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Here's something to think about: What could you do to make the lamp more efficient ? Answer: Use it for a heater !
If you use it for a heater, then the HEAT is the 'useful' part, and the light is the part that you really don't care about. Suddenly ... bada-boom ... the lamp is 90% efficient !
History is open to ongoing and changing interpretations because changing <span>values limit interpretation.
So your answer is A.</span>
Answer: C. T
Explanation:
Period is a unit of time; and in the context of waves or oscillations it is defined as <em>"the </em><u><em>time </em></u><em>elapsed between two equivalent points on the wave or oscillation".</em>
<em />
It is important to note Period (denoted by 
) is one of the most important factors (along with the amplitude, frequency and velocity) to describe and characterize a wave.
In addition, Period has an inverse relation with the frequency 
, this means that if we are given the frequency of a wave, we can inmediatly know its Period.
A=atomic mass
Z=atomic number (nº of protons).
N=neutons.
A=Z+N
Data:
A=39
Z=19
A=Z+N
39=19+N
N=39-19=20.
It therefore has 20 neutrons in its nucleus.
