Tag: properties of material substances

Quizzes (4) Questions (125)

Questions Related to properties of material substances

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

Which of the following is an example of plastic deformation?

  1. stretching a rubber band

  2. stretching salt water taffy

  3. none

  4. both
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Whenever a deforming force is applied to a non-rigid substance, the substance undergoes deformation in dimension or shape. Elastic substances are those which come back to their original shape or dimensions after the deformation force is removed. Plastic substances are those which do not come back to their original shape or dimensions even after the deformation force is removed.

Salt water taffy is a plastic material. Hence stretching of it will be a plastic deformation. Rubber-band is an elastic material.

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

Which of the following are close to ideal plastics?

  1. Putty

  2. Mud

  3. Rubber band

  4. None of the above
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation

Whenever a deforming force is applied to a non-rigid substance, the substance undergoes deformation in dimension or shape. Plastic substances are those which do not come back to their original shape or dimensions even after the deformation force is removed.
Substances like clay, putty, mud etc., are highly plastic in nature

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

Which of the following is not artificial form of plastics?

  1. Nylon

  2. Teflon

  3. Styrofoam

  4. None of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Plastic is a synthetic material made from a wide range of organic polymers such as polyethylene, PVC, nylon, etc., that can be moulded into shape while soft, and then set into a rigid or slightly elastic form. 

Nylon, teflon and styrofoam are all examples of plastics.

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

The property of a material due to which shape is changed permanently is known as:

  1. Elasticity

  2. Plasticity

  3. Ductility

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The property of a body to regain its original shape when the deforming force is removed from it or to oppose the change in its original shape is called elasticity.

Plasticity is the property of a material not to regain its original shape when the deforming force is removed, i e. a deforming force changes the shape of material permanently. 
Ductility is commonly defined as the ability of a body to be stretched into wires.

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

 Plastic deformation results from the following 

  1. Slip

  2. Twinning

  3. Both slip and twinning

  4. creep
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Two prominent mechanisms of plastic deformation, namely slip and twinning occur . 
1. Slip involves sliding of blocks of crystal over one other along definite crystallographic planes, called slip planes. During slip each atom usually moves same integral number of atomic distances along the slip plane producing a step, but the orientation of the crystal remains the same.

2. Portion of crystal takes up an orientation that is related to the orientation of the rest of the untwined lattice in a definite, symmetrical way. The twinned portion of the crystal is a mirror image of the parent crystal.

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

A thin metal sheet is being bent by or pounded in to a new shape. The process of being elastic to plastic behaviour is known as 

  1. Yield

  2. Creep

  3. Welding

  4. Tinkering
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The yield point is the point on a stressstrain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Yielding means the start of breaking of fibers.

The correct option is option(a)

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

The plasticity behaviour of a material determines the 

  1. elastic behavior of the material

  2. resistance of the material to electric fields

  3. viscous behavior of the material and is irrecoverable.

  4. resistance of the material to magnetic fields
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Plasticity is defined as the property which enables a material to be deformed continuously and permanently without rupture during the application of force. This deformation determines the viscous behavior of the material and is irrecoverable.

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

Plastic deformation in a material begins at

  1. Q point

  2. Yield point

  3. Proportionality limit

  4. Elastic limit
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Beyond the elastic limit, permanent deformation will occur. The elastic limit is therefore the lowest stress point at which permanent deformation can be measured. At yield point, permanent deformation occurs or the substance becomes plastic.

The correct option is option (b)

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

At yield point, Hooke's law doesn't hold good

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The yield point is the point on a stressstrain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Yielding means the start of breaking of fibers.

Thus, Hooke's law dosent hold good in this region, as stress is not proportional to strain in this region