【单选题】20 / 40若E=3.0×104 MPaE=3.0\times 10^{4}\,\mathrm{MPa}E=3.0×104MPa,φ=2.0\varphi=2.0φ=2.0,χ=0.8\chi=0.8χ=0.8,则EφE_{\varphi}Eφ约为?A1.15×104 MPa1.15\times 10^{4}\,\mathrm{MPa}1.15×104MPa正确B3.0×104 MPa3.0\times 10^{4}\,\mathrm{MPa}3.0×104MPaC6.0×104 MPa6.0\times 10^{4}\,\mathrm{MPa}6.0×104MPaD0.8×104 MPa0.8\times 10^{4}\,\mathrm{MPa}0.8×104MPa参考答案A参考解析Eφ=E/(1+1.6)=E/2.6≈1.15×104 MPaE_{\varphi}=E/(1+1.6)=E/2.6\approx 1.15\times 10^{4}\,\mathrm{MPa}Eφ=E/(1+1.6)=E/2.6≈1.15×104MPa。