a brass rod is 2 m long at a certain temperature. what is its length for a temperature rise of 100 K, if the expansivity of brass is 18 *10^-6K-1?

I don't have an idea am just helping a kid who is in ss1

To find the change in length of the brass rod, we can use the formula:

ΔL = α * L0 * ΔT

Where:
ΔL is the change in length
α is the coefficient of linear expansion (expansivity)
L0 is the original length of the rod
ΔT is the change in temperature

Given:
The original length of the brass rod (L0) = 2 m
The change in temperature (ΔT) = 100 K
The coefficient of linear expansion (α) for brass = 18 * 10^-6 K^-1

Substituting these values into the formula:

ΔL = (18 * 10^-6 K^-1) * (2 m) * (100 K)

Now we can calculate the change in length:

ΔL = 36 * 10^-6 m * 100 K

ΔL = 0.0036 m

Therefore, the change in length of the brass rod for a temperature rise of 100 K is 0.0036 meters.