Question Text
Question 1 :
The property to restore the natural shape or to oppose the deformation is called :
Question 2 :
<span>The property of a material due to which shape is changed permanently is known as:</span><br/>
Question 4 :
A toy car travels in a horizontal circle of radius 2a, kept on the track by a radial elastic string of unstretched length a. The period of rotation is T. Now the car is speeded up until it is moving in a circle of radius 3a. Assuming that the string obeys Hooke's law then the new period will be
Question 5 :
Consider the following two statements A and B and identify the correct answer .<br>A) A metal wire held vertically is longer than when it placed on a horizontal table.<br>B) Due to its own weight, some elongation is produced when it is held vertically.
Question 6 :
Assertion (A): Stress is restoring force per unit area.<br/>Reason (R) : Interatomic forces in solids are <span>responsible for the property of elasticity</span>
Question 7 :
Assertion: When a rod is pulled by a force acting on one end (longitudinally) then there will be no longitudinal stress in the rod. (Assume surface is friction-less )
Reason: Longitudinal stress is internal normal force per unit area.
Question 9 :
Two exactly similar wires of steel and copper are stretched by equal forces. If the total elongation is 2cm, then how much is the elongation in steel and copper wire respectively? Given Y$_{steel}$ =20 x 10$^{11}$ dyne/cm$^2$ , $Y_{copper}$ = 12 x 10$^{11}$ dyne/cm$^2$.
Question 11 :
The length of a rubber cord is $l_1$ metres when the tension in it is $4N$ and $l_2$ metres when the tension is $5N$. then the length in meters when the tension is $9N$ is