Why are Watt Hours not Watts per Hour? Are they the same thing?
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They are not that same thing. Watt-hours are watts x hours, and watts per hour is watts / hours.
A watt is an amount of energy per time. Multiply that by a unit of time, and you get the amount of energy.
Watts per hour is a little harder to wrap you head around. It’s a measure of how fast the flow of energy is changing. A positive value means that the flow of energy is increasing with time, and a negative value that it’s decreasing with time.
No, watts per hour and watt hours are not the same thing. Watts per hour would be W/h and watt hours is W*h.
Top explain what both mean, I’ll first explain what both components mean:
Hours are a measure of time (not so hard I guess)
A Watt is a measure of power. It says something about the rate at which energy is transferred.
A Wh (watt hour) is energy (just like calories and joules). Energy is the ability to change things. Like heating up stuff or move an object.
Here is an example to show this.
Heating up a pot of water takes energy. You transfer energie from a heatsource into the water. It takes a 1000 calories (or 1.16222222 watt hours) to heat up 1 kilogram of water with 1 Kelvin. This transfer of doesn’t happen instantaneously, it takes time. If it takes 1 hour to change the temperature of this pot of water, then the power with which this water is heated would be 1.16/1= 1.16 watt. If you want to do it faster, you need to increase the power.
So energy is power applied for some time (Wh=W x h, or in your school textbook: E=P x t) and consequently; power is energy over time (Wh/h=W or in your school books it would be P=E/t)
So what would W/h be?
This would mean that power would change over time in a linear way. To stay with the same example as above. If you would gradually turn the knob of the stove to get the water to heat up faster than you would change the power over time which is weird to do in a linear fashion.
No, watts per hour and watt hours are not the same thing. Watts per hour would be W/h and watt hours is W*h.
Top explain what both mean, I’ll first explain what both components mean:
Hours are a measure of time (not so hard I guess)
A Watt is a measure of power. It says something about the rate at which energy is transferred.
A Wh (watt hour) is energy (just like calories and joules). Energy is the ability to change things. Like heating up stuff or move an object.
Here is an example to show this.
Heating up a pot of water takes energy. You transfer energie from a heatsource into the water. It takes a 1000 calories (or 1.16222222 watt hours) to heat up 1 kilogram of water with 1 Kelvin. This transfer of doesn’t happen instantaneously, it takes time. If it takes 1 hour to change the temperature of this pot of water, then the power with which this water is heated would be 1.16/1= 1.16 watt. If you want to do it faster, you need to increase the power.
So energy is power applied for some time (Wh=W x h, or in your school textbook: E=P x t) and consequently; power is energy over time (Wh/h=W or in your school books it would be P=E/t)
So what would W/h be?
This would mean that power would change over time in a linear way. To stay with the same example as above. If you would gradually turn the knob of the stove to get the water to heat up faster than you would change the power over time which is weird to do in a linear fashion.
Watt hours are a unit of energy or work. A Watt is a unit of power which is the rate of doing work. Watt hours or actually kilowatt hours are used to measure a quantity of electrical energy used. The cost of electricity is based on measuring this. A Watt is measure of how fast work (force times distance) can be done. Car engines could be rated in Watts rather than horsepower. Watt hours is like how much gasoline you burn over a period of time.
Watt hours are a unit of energy or work. A Watt is a unit of power which is the rate of doing work. Watt hours or actually kilowatt hours are used to measure a quantity of electrical energy used. The cost of electricity is based on measuring this. A Watt is measure of how fast work (force times distance) can be done. Car engines could be rated in Watts rather than horsepower. Watt hours is like how much gasoline you burn over a period of time.
They are not that same thing. Watt-hours are watts x hours, and watts per hour is watts / hours.
A watt is an amount of energy per time. Multiply that by a unit of time, and you get the amount of energy.
Watts per hour is a little harder to wrap you head around. It’s a measure of how fast the flow of energy is changing. A positive value means that the flow of energy is increasing with time, and a negative value that it’s decreasing with time.
They’re not the same thing, one is multiplication, the other is division.
Watts are a unit of power.
Joules are a unit of energy.
1 Watt = 1 Joule per second.
Watt hours are units of energy.
1 Watt hour = 3600J.
There are 3600 seconds in an hour, so that’s how many joules of energy you would use if you left a 1 watt load powered for 1 hour.
Watts per hour is not a commonly used unit. It would describe the rate of change in power. For example, if you have a machine that’s using 10w, 1 hour from now, it uses 15w, and an hour later you’re using 20, the power would be changing at 5W/hr.
They are not that same thing. Watt-hours are watts x hours, and watts per hour is watts / hours.
A watt is an amount of energy per time. Multiply that by a unit of time, and you get the amount of energy.
Watts per hour is a little harder to wrap you head around. It’s a measure of how fast the flow of energy is changing. A positive value means that the flow of energy is increasing with time, and a negative value that it’s decreasing with time.
They’re not the same thing, one is multiplication, the other is division.
Watts are a unit of power.
Joules are a unit of energy.
1 Watt = 1 Joule per second.
Watt hours are units of energy.
1 Watt hour = 3600J.
There are 3600 seconds in an hour, so that’s how many joules of energy you would use if you left a 1 watt load powered for 1 hour.
Watts per hour is not a commonly used unit. It would describe the rate of change in power. For example, if you have a machine that’s using 10w, 1 hour from now, it uses 15w, and an hour later you’re using 20, the power would be changing at 5W/hr.
They’re not the same thing, one is multiplication, the other is division.
Watts are a unit of power.
Joules are a unit of energy.
1 Watt = 1 Joule per second.
Watt hours are units of energy.
1 Watt hour = 3600J.
There are 3600 seconds in an hour, so that’s how many joules of energy you would use if you left a 1 watt load powered for 1 hour.
Watts per hour is not a commonly used unit. It would describe the rate of change in power. For example, if you have a machine that’s using 10w, 1 hour from now, it uses 15w, and an hour later you’re using 20, the power would be changing at 5W/hr.
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