Please help!!!!

The other answer on Chegg was incorrect so please redo!

The simplest way to choose the best materials for a structural application are to consider 2 key parameters: the elastic modulus (i.e. linear and recoverable behavior), and the strengh (related to stresses and eventually failure).

In MSE, we often analyze these parameters using flexural tests. These typically correlate applied loads (forces) and displacements or dieflections (e.g. 3-point bending). As an example:

Consider a 20 meter long bridge, simply supported at each end.

The primary beam for the bridge, which flexes upon loading, has a square cross section that is 30 cm on a side.

This beam is made of concrete (which has a typical elastic modulus of 60 GPa)

When a car weighing 1000 kg is at the very center of the beam (and you can reasonably assume the entire load is applied just at the very center point), what will be the midpoint deflection of the beam (in cm)?

Remember F=ma, and a is gravitational acceleration. Watch your units.

Response Feedback:

This may help:

term	value	units
mass	1000	kg
gravity	9.8	m/s^2
modulus	60	GPa
L	20	m
b	30	cm
d	30	cm
GPa to Pa	1E+09	Pa/GPa
cm to m	100	cm/m
Force	9800	N