Question 2 :
Assertion: The strain present in the material after unloading is called the residual strain or plastic strain and the strain disappears during unloading is termed as recoverable or elastic strain.
Reason: After yieild point, there is some residual stress left in an material on unloading.
Question 3 :
A material has poisson's ratio 0.5. If a uniform rod of it suffers a longitudinal strain of $3\times { 10 }^{ -3 }$, what will be percentage increase in volume?
Question 5 :
A material has Poisson's ratio $0.5$. if a uniform rod of it suffers a longitudinal strain of $2\times {10}^{3}$, then the percentage change in volume is
Question 6 :
The area of cross-section of a steel wire $\left( Y=2.0\times { 10 }^{ 11 }{ N }/{ { m }^{ 2 } } \right)$ is $0.1 { cm }^{ 2 }$. The force required to double its length will be :
Question 7 :
The dimensions of four wires of the same material are given below. In which wire the increase in the length will be maximum?
Question 8 :
The gale blows over a house. The force due to gale on the roof is:-
Question 9 :
A water drop takes the shape of a sphere in a oil while the oil drop spreads in water, because ( A.F, = adhesive force ,C.F. = cohesive force )
Question 10 :
Assertion: The velocity of flow of a liquid is smaller when pressure is larger and vice-versa.
Reason: According to Bernoulli's theorem, for the stream line flow of an ideal liquid, the total energy per unit mass is not constant.
Question 11 :
The volume of liquid flowing per second out of an orifice at the bottom of the tank does not depend upon:
Question 12 :
When a sphere falling in a viscous fluid attains a terminal velocity, then:
Question 13 :
What should be the ratio of area of cross section of the master cylinder and wheel cylinder of a hydraulic brake so that a force of $15 N$ can be obtained at each of its brake shoe by exerting a force of $0.5 N$ on the pedal?
Question 14 :
The surface energy of a liquid drop is $E$. It is sprayed into $1000$ equal droplets. The work done in spraying is<br>
Question 15 :
If there were no atmosphere around the earth, the temperature of the earth will
Question 16 :
State whether given statement is True or False<br/>The heat coming from the sun travels by convection
Question 17 :
Two copper spheres of radii $6 cm$ and $12 cm$ respectively are suspended in an evacuated enclosure. Each of them are at a temperature $15^0 C$ above the surroundings. The ratio of their rate of loss of heat is ___________.
Question 19 :
When a hot enclosure is viewed from a small opening in it, their radiations appear predominantly bright red. Now if a green glass piece is placed in the enclosure, then after some time, the glass piece will appear<br>
Question 20 :
The correct statement of the following:<br>A) Water can be boiled inside the artificial satellite by convection<br>B) Heavy liquid can be boiled in artificial satellite by convection<br>Mark correct option/s