Physics 2013 JAMB Past Questions - Question 17: A wire of length 100.0m at 30degree has linear expansivity of 2x10-¹ Calculate the length of the wire at a temperature of -10degree

Correct Answer

D

Explanation

To calculate the length of the wire at a temperature of -10 degrees Celsius, we can use the formula for linear expansion:

ΔL = α * L * ΔT

Where:
ΔL is the change in length
α is the linear expansivity
L is the original length
ΔT is the change in temperature

Given:
L = 100.0 m (original length)
α = 2x10^(-1) (linear expansivity)
ΔT = -10 - 30 = -40 degrees Celsius (change in temperature)

Plugging in the values, we can calculate the change in length:

ΔL = (2x10^(-1)) * (100.0) * (-40)
ΔL = -800.0 m

To find the final length, we add the change in length to the original length:

Final length = L + ΔL
Final length = 100.0 m + (-800.0 m)
Final length = -700.0 m

Therefore, the length of the wire at a temperature of -10 degrees Celsius is -700.0 meters.