Horizontal component = (10N) · sin (20°) = 3.42... N (rounded)
Vertical component = (10N) · cos (20°) = 9.39... N (rounded)
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 !
Answer:
astronauts age is 32 years
correct option is e 32 years
Explanation:
given data
travels = 20 light year
stay = 2 year
return = 52 years
to find out
astronauts aged
solution
we know here they stay 2 year so time taken in traveling is
time in traveling = ( 52 -2 ) = 50 year
so it mean 25 year in going and 25 years in return
and distance is given 20 light year
so speed will be
speed = distance / time
speed = 20 / 25 = 0.8 light year
so time is
time = 
time = 
time = 15 year
so age is 15 + 2 + 15
so astronauts age is 32 years
so correct option is e 32 years