On a day that the temperature is 10.0°C, a concrete walk is poured in such a way that the ends of the walk are unable to move. Take Young's modulus for concrete to be 7.00 109 N/m2 and the compressive strength to be 2.00 109 N/m2. (The coefficient of linear expansion of concrete is 1.2 10-5(°C−1).) What is the stress in the cement on a hot day of 42.0°C? N/m2

The stress is  

Explanation:

From the question we are told that

    The first temperature is  

    The  young modulus is  

    The compressive strength is  

     The coefficient of  linear expansion is  

     The  second temperature is  

Generally the change in length of the concrete is mathematically represented as

=>  

=>

Now  the young modulus is  mathematically represented as

=>    

=>  

=>  

=>  

a and c

c is 100% but i am confused in a