A specimen of copper having a rectangular cross section 15.2 mm * 19.1 mm (0.60 in. * 0.75 in.) is pulled in tension with 44,500 N (10,000 lbf ) force, producing only elastic deformation. Calculate the resulting strain.

The elastic modulus for Cu is given in Table 7.1 as 110 GPa (or 110* 10^9 N/m2).

Strain of the copper specimen will be equal to 0.0013

Explanation:

We have given tension in the wire

Area of rectangular copper specimen

We have to find the strain of the copper specimen

Stress will be equal to

Elastic modulus of copper is given

Modulus of elasticity is equal to

So

Strain = 0.0013

So strain of the copper specimen will be equal to 0.0013  

a) = 6.6m/s

b) = 125.15°

Explanation:

Speed of the boat =3.8m/s

width of the both = 220m

speed of boat relative to water = 3.8m/s, 35°

Relative Velocities V₀ = V₁ + V₂

V₀ = Velocity of the boat relative to ground

V₁ = Velocity of the boat relative to river

V₂ = Velocity of the river relative to ground

V₁ = Velocity of the boat relative to river = -4.47i + 6.55j

V₀ = Velocity of the boat relative to ground

= (-4.47i + 6.55j) + (3.8i)

= (0.67i + 6.55j)m/s

Magnitude V₀

/V₀/ = √(0.67² + 6.55²)

= 6.6m/s

b)

Direction of the boat relative to ground

cosθ= -V₂ / /V₀/

cosθ = -3.8 / 6.6

θ = 125.15°