if a steel flagpole get 5.1 mm taller when temperature increase by 5.0 degree celsius approximately how tall is the flagpole?

Look up the coefficient of thermal expansion of steel. Call it a.

a*L*(deltaT) = 0.0051 meters

Solve for L.
L = 0.0051/(a*deltaT)
"deltaT" = 5 C

To find the approximate height of the flagpole, we can use the concept of thermal expansion.

Thermal expansion is the tendency of a substance to change its shape, volume, or length in response to a change in temperature. In this case, the steel flagpole expands in length when the temperature increases.

We are given that the flagpole gets 5.1 mm taller when the temperature increases by 5.0 degrees Celsius. This means that for every 5.0 degrees Celsius increase in temperature, the flagpole increases in height by 5.1 mm.

To calculate the approximate height of the flagpole, we need to know the actual increase in temperature. Without this information, we cannot directly determine the height.

If you provide the actual increase in temperature, we can use the given information to find the height of the flagpole.