Hooke's Law, Density and Force-Extension Graphs

What is the equation for Hooke's Law?

• F = kΔL

• F = kL

• F = 1/2k(ΔL)²

• F = k/ΔL

What is A on the graph?

• Spring Constant

• Young's Modulus

• Elastic Limit

• Limit of Proportionality

A wire is stretched by 0.08m when 28N is applied. What is the stiffness constant of the wire?

• 290Nm^-1

• 350Nm^-1

• 290Nm^-2

• 350Nm^-2

What does the area under a force-extension graph represent?

• Young's Modulus

• Strain Energy

• Elastic Potential Energy

• Work Done

Wire with length 0.2m, force of 55N is applied and the wire extends to 310mm. Calculate ΔL

• 11mm

• 11m

• 0.11cm

• 0.11m

What is the point B on the force-extension graph?

• Elastic limit

• Yield point

• Plastic limit

• Limit of proportionality

A solid aluminium cylinder has volume 9.1 x 10^-4 m³. The density is 2700 kgm^-3. What is the mass to 2 s.f?

• 3.0kg

• 2.5kg

• 2.4kg

• 2.0kg

A rubber band is loaded with weights, and produced the graph shown, where A is loading and B is unloading. Does the rubber band obey Hooke's law?

• Yes

• No

What is plastic deformation?

• A material returns to its original length once forces are removed

• A material is permanently stretched once the forces are removed

A force of 2.0N is applied to a spring, and it stretches by 0.30m. How much will a 6.0N force extend the spring by?

• 0.10m

• 0.30m

• 0.60m

• 0.90m