Wavelength = velocity/frequency
wavelength = v/f
v= 13km/s = change this to m/s = 13000m/s
f= 14Hz
wavelength = 13000m/s÷14Hz =928.7 m
' W ' is the symbol for 'Watt' ... the unit of power equal to 1 joule/second.
That's all the physics we need to know to answer this question.
The rest is just arithmetic.
(60 joules/sec) · (30 days) · (8 hours/day) · (3600 sec/hour)
= (60 · 30 · 8 · 3600) (joule · day · hour · sec) / (sec · day · hour)
= 51,840,000 joules
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Wait a minute ! Hold up ! Hee haw ! Whoa !
Excuse me. That will never do.
I see they want the answer in units of kilowatt-hours (kWh).
In that case, it's
(60 watts) · (30 days) · (8 hours/day) · (1 kW/1,000 watts)
= (60 · 30 · 8 · 1 / 1,000) (watt · day · hour · kW / day · watt)
= 14.4 kW·hour
Rounded to the nearest whole number:
14 kWh
B. gas has no definite shape or volume. liquid has definite volume but no definite shape
First of all, the formula for speed is;
Speed=distance/time
From the question, you have;
distance=7,200km
Time=9 hours
So that will be;
Speed=7200/9
When divided, you will have;
Speed=800
The unit for speed is km/hr or m/s. So that will be;
Speed=800km/hr
Hope that helped, have a nice day