If you run at a constant speed of 7.5 m/s, how long does it take for you to finish a 100 m race ? show your work
1 answer:
You might be interested in
The power expended is 500 W
Explanation:
First of all, we start by calculating the work done by the man in order to ascend: this is equal to the gravitational potential energy gained by the man, which is
where
m = 50 kg is the mass of the man
is the acceleration of gravity
is the change in height
Substituting,
Now we can calculate the power expended, which is given by
where
W = 2500 J is the work done
t = 5 s is the time elapsed
Substituting, we find
Learn more about power:
#LearnwithBrainly
When the capacitor is connected to the voltage, a charge Q is stored on its plates. Calling the capacitance of the capacitor in air, the charge Q, the capacitance
and the voltage (
) are related by
(1)
when the source is disconnected the charge Q remains on the capacitor.
When the space between the plates is filled with mica, the capacitance of the capacitor increases by a factor 5.4 (the permittivity of the mica compared to that of the air):
this is the new capacitance. Since the charge Q on the plates remains the same, by using eq. (1) we can find the new voltage across the capacitor:
And since , substituting into the previous equation, we find: