materials-mcq-old-question

A student applied a range of forces to the ends of a copper wire and measured the corresponding new length of the wire. The force-extension graph for the wire is shown. What is the maximum force that could be applied and then removed such that the wire would go back to its original length?

• 200 N

• 300 N

• 400 N

• 500 N

A girl dropped a stone into an empty well. She heard the sound of the stone hitting the bottom of the well after 4 seconds. The depth of the well is about

• 20 m

• 40 m

• 80 m

• 160 m

A solid cylinder of diameter 0.025m is placed on a table. A force is applied to the cylinder, as shown. The stress in the cylinder, in pascals, can be calculated using

Which of the following displacement-time graphs shows a particle starting from rest and reaching terminal velocity?

• A

• B

• C

• D

A spring is stretched by a force F. The energy stored in the spring is E. The spring is connected to a second identical spring. The combination is stretched by the same force F as shown. Which of the following is the total energy stored in the combination of two springs?

• E

• 2E

• 4E

A thin wire of uniform cross-sectional area is stretched by an increasing force. The corresponding stress-strain graph is shown. Points w, x, y, and z are shown on the graph. Select the row of the table that correctly identifies the yield point, the limit of proportionality, and the elastic limit.

• A

• B

• C

• D

A student drops small solid spheres through a liquid of viscosity η in a measuring cylinder. A small sphere of volume V falls at terminal velocity through the liquid. A larger sphere of volume 8 V is made of a different material. The larger sphere falls through the liquid at the same terminal velocity. The frictional force acting on the small sphere is F. Which of the following is the frictional force acting on the larger sphere?

• 512F

• 8F

• 2F

• F

A specimen of a material was fixed at one end and subjected to a tensile force of 60 N. The length of the specimen became 9.0 cm as shown. The force was increased to 100 N. The length of the specimen became 11.0 cm. The specimen obeyed Hooke's law throughout. Which of the following was the original length, in cm, of the specimen before any force was applied?

• 6.0

• 7.0

• 8.0

• 9.0

A student investigated Hooke's law using the equipment shown. As each additional load was added, the new position of a marker along a metre rule was recorded and the extension calculated. The investigation was repeated with an additional identical spring, arranged as shown. For a given applied load, which of the following statements is correct?

• A. The extension is doubled because the spring constant is doubled.

• B. The extension is doubled because the spring constant is halved.

• C. The extension is halved because the spring constant is doubled.

• D. The extension is halved because the spring constant is halved.

Which of the following is a correct unit for stiffness of a spring?

• kg m⁻¹

• kg s⁻²

• N m

• N s