Tag: elastic behaviour of solids

Questions Related to elastic behaviour of solids

Which of the following statements is incorrect?

chemistry substances in the surroundings - their states and properties elastic behaviour of solids elastic and plastic substances properties of substances

  1. When a material is under tensile stress, the restoring forces are caused by interatomic attraction while under compressional stress, the restoring force is due to interatomic repulsion

  2. The stretching of a coil is determined by its shear modulus

  3. Rubber is more elastic than steel

  4. Shearing stress plays an important role in the buckling of shafts

Show answer
Correct Option: C
Explanation:

More elastic means, the value of an elastic constant is more and. Steel have move elastic constant in compare to Rubber, So Steel is more elastic than rubber.
All other statements are correct.

Out of the following whose elasticity is independent of temperature

chemistry substances in the surroundings - their states and properties elastic behaviour of solids elastic and plastic substances properties of substances

  1. steel

  2. copper

  3. Invar steel

  4. glass

Show answer
Correct Option: C
Explanation:

For most of the materials, elasticity decreases with temperature. One exception is invar steel.

Which of the following is an example of plastic deformation?

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

  1. stretching a rubber band

  2. stretching salt water taffy

  3. none

  4. both

Show answer
Correct Option: B
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.

Which of the following are close to ideal plastics?

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

  1. Putty

  2. Mud

  3. Rubber band

  4. None of the above

Show answer
Correct Option: A,B
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

Which of the following is not artificial form of plastics?

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

  1. Nylon

  2. Teflon

  3. Styrofoam

  4. None of the above

Show answer
Correct Option: D
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.

Fill in the blank.
In a technical sense a substance with a ________ elasticity is one that requires a ______  force to produce a distortion-for example, a steel sphere. 

chemistry substances in the surroundings - their states and properties elastic behaviour of solids elastic and plastic substances properties of substances

  1. high, small

  2. high, large

  3. low, large

  4. low , small

Show answer
Correct Option: B
Explanation:

According to Hooke's law, within elastic limit,

    $E=\dfrac{stress}{strain}$$=\dfrac{deforming\ force}{(area\times strain)}$ 
It means higher the elasticity, larger will be the required deforming force.
Hence, in a technical sense a substance with a high elasticity is one that requires a high force to produce a distortion.

As compared to concrete, steel has compressive strength:

chemistry substances in the surroundings - their states and properties elastic behaviour of solids elastic and plastic substances properties of substances

  1. $25$ times less

  2. equal

  3. $25$ times more

  4. $5$ times more

Show answer
Correct Option: C
Explanation:

Compressive strength is the capacity of a material or structure to withstand loads tending to reduce size, as opposed to tensile strength, which withstands loads tending to elongate.

Compressive strength is one of the most important engineering property of Concrete which designers are concerned of. However the compressive strength of steel is around 25 time more than that of concrete.

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

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

  1. Elasticity

  2. Plasticity

  3. Ductility

  4. None of the above

Show answer
Correct Option: B
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.

Elasticity is defined as the ability of a body to 

chemistry substances in the surroundings - their states and properties elastic behaviour of solids elastic and plastic substances properties of substances

  1. Resist linear motion in a hard surface

  2. Resist rolling motion in a hard surface

  3. Resist a distorting influence and to return to its original size and shape when that influence or force is removed.

  4. Resist electric current in a magnetic field

Show answer
Correct Option: C
Explanation:

Elasticity is defined as the ability of a body to  resist a distorting influence and to return to its original size and shape when that influence or force is removed.

Substances that elongate considerably and undergo plastic deformation before they break are known as

chemistry substances in the surroundings - their states and properties elastic behaviour of solids elastic and plastic substances properties of substances

  1. brittle substances

  2. breakable substances

  3. ductile substances

  4. all of these

Show answer
Correct Option: C
Explanation:

Substances that elongate considerably and undergo plastic deformation before they break are known as ductile substances