# Convert phot to watt / square meter

Learn how to convert 1 phot to watt / square meter step by step.

## Calculation Breakdown

Set up the equation
$$1.0\left(phot\right)={\color{rgb(20,165,174)} x}\left(\dfrac{watt}{square \text{ } meter}\right)$$
Define the base values of the selected units in relation to the SI unit $$\left(lux\right)$$
$$\text{Left side: 1.0 } \left(phot\right) = {\color{rgb(89,182,91)} 10^{4}\left(lux\right)} = {\color{rgb(89,182,91)} 10^{4}\left(lx\right)}$$
$$\text{Right side: 1.0 } \left(\dfrac{watt}{square \text{ } meter}\right) = {\color{rgb(125,164,120)} 683.0\left(lux\right)} = {\color{rgb(125,164,120)} 683.0\left(lx\right)}$$
Insert known values into the conversion equation to determine $${\color{rgb(20,165,174)} x}$$
$$1.0\left(phot\right)={\color{rgb(20,165,174)} x}\left(\dfrac{watt}{square \text{ } meter}\right)$$
$$\text{Insert known values } =>$$
$$1.0 \times {\color{rgb(89,182,91)} 10^{4}} \times {\color{rgb(89,182,91)} \left(lux\right)} = {\color{rgb(20,165,174)} x} \times {\color{rgb(125,164,120)} {\color{rgb(125,164,120)} 683.0}} \times {\color{rgb(125,164,120)} \left(lux\right)}$$
$$\text{Or}$$
$$1.0 \cdot {\color{rgb(89,182,91)} 10^{4}} \cdot {\color{rgb(89,182,91)} \left(lx\right)} = {\color{rgb(20,165,174)} x} \cdot {\color{rgb(125,164,120)} 683.0} \cdot {\color{rgb(125,164,120)} \left(lx\right)}$$
$$\text{Cancel SI units}$$
$$1.0 \times {\color{rgb(89,182,91)} 10^{4}} \cdot {\color{rgb(89,182,91)} \cancel{\left(lx\right)}} = {\color{rgb(20,165,174)} x} \times {\color{rgb(125,164,120)} 683.0} \times {\color{rgb(125,164,120)} \cancel{\left(lx\right)}}$$
$$\text{Conversion Equation}$$
$$10^{4} = {\color{rgb(20,165,174)} x} \times 683.0$$
Switch sides
$${\color{rgb(20,165,174)} x} \times 683.0 = 10^{4}$$
Isolate $${\color{rgb(20,165,174)} x}$$
Multiply both sides by $$\left(\dfrac{1.0}{683.0}\right)$$
$${\color{rgb(20,165,174)} x} \times 683.0 \times \dfrac{1.0}{683.0} = 10^{4} \times \dfrac{1.0}{683.0}$$
$$\text{Cancel}$$
$${\color{rgb(20,165,174)} x} \times {\color{rgb(255,204,153)} \cancel{683.0}} \times \dfrac{1.0}{{\color{rgb(255,204,153)} \cancel{683.0}}} = 10^{4} \times \dfrac{1.0}{683.0}$$
$$\text{Simplify}$$
$${\color{rgb(20,165,174)} x} = \dfrac{10^{4}}{683.0}$$
Solve $${\color{rgb(20,165,174)} x}$$
$${\color{rgb(20,165,174)} x}\approx14.641288433\approx14.6413$$
$$\text{Conversion Equation}$$
$$1.0\left(phot\right)\approx{\color{rgb(20,165,174)} 14.6413}\left(\dfrac{watt}{square \text{ } meter}\right)$$