Answer:
there will be a heat flow from water to the metal ball...
Answer:
Explanation:
The pail is rotated at a constant rate in vertical circular path so it has the minimum speed at all points along its circular path . That means at top position the velocity is almost zero. In that case the centripetal force at top position will be provided by its weight or
mg = mv² / r ( r is radius of vertical circular path )
v = √ rg
At the bottom position its velocity will be increased due to loss of potential energy
so 1/2 m V² = 1/2 m v² + mg x 2r
V =√ 5 gr
If R be the reaction force at the bottom by bottom of pail
R - mg = mV² / r
R = mg +mV² / r
= mg + m x 5gr / r
R = 6mg
This is the magnitude of the force exerted by the water on the bottom of the pail .
' 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
__________________________________
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
Answer:
a) E=228391.8 N/C
b) E=-59345.91N/C
Explanation:
You can use Gauss law to find the net electric field produced by both line of charges.
Where E1 and E2 are the electric field generated at a distance of r1 and r2 respectively from the line of charges.
The net electric field at point r will be:
a) for y=0.200m, r1=0.200m and r2=0.200m:
![E=\frac{1}{2\pi(8.85*10^{-12}C^2/Nm^2)}[\frac{4.80*10^{-6}C}{0.200m}-\frac{2.26*10^{-6}C}{0.200m}}]=228391.8N/C](https://tex.z-dn.net/?f=E%3D%5Cfrac%7B1%7D%7B2%5Cpi%288.85%2A10%5E%7B-12%7DC%5E2%2FNm%5E2%29%7D%5B%5Cfrac%7B4.80%2A10%5E%7B-6%7DC%7D%7B0.200m%7D-%5Cfrac%7B2.26%2A10%5E%7B-6%7DC%7D%7B0.200m%7D%7D%5D%3D228391.8N%2FC)
b) for y=0.600m, r1=0.600m, r2=0.200m:
![E=\frac{1}{2\pi(8.85*10^{-12}C^2/Nm^2)}[\frac{4.80*10^{-6}C}{0.600m}-\frac{2.26*10^{-6}C}{0.200m}}]=-59345.91N/C](https://tex.z-dn.net/?f=E%3D%5Cfrac%7B1%7D%7B2%5Cpi%288.85%2A10%5E%7B-12%7DC%5E2%2FNm%5E2%29%7D%5B%5Cfrac%7B4.80%2A10%5E%7B-6%7DC%7D%7B0.600m%7D-%5Cfrac%7B2.26%2A10%5E%7B-6%7DC%7D%7B0.200m%7D%7D%5D%3D-59345.91N%2FC)
Answer:
True statements:
Power is the rate at which work is done.
Power is the rate at which energy is transformed.
The SI unit of power is watt.
A person is limited in the total work he or she can do by the rate at which energy can be transformed.
Explanation:
The above statements are true.
1. Power is defined as the rate at which work is done.
2. Power is the rate at which energy is transformed. Whenever energy changes its form, or moves from one place to another, the rate at which it makes those changes is described as power.
3. The SI Unit of power is watts. If 1 joule of energy is converted by an object in 1 second then its power is called one watt.
So, the statement<em> 'the SI unit of power is the horsepower' is</em> false.
4. A person is limited in the total work he or she can do by the rate at which energy can be transformed i.e, his power. He is not only limited by the total energy required.
So, the statement <em>'A person is limited in the total work he or she can do only by the total energy required'</em> is not completely true.
