Minimum and maximum values of Poisson's ratio for a metal lies between:
- ∞ to + ∞
0 to 1
- ∞ to 1
0 to 0.5
A wire of diameter 1 mm breaks under a tension of 1000 N. Another wire, of same material as that of the first one, but of diameter 2 mm, breaks under a tension of :
500 N
100 N
1000 N
4000 N
In a capillary tube experiment, a vertical, 30 cm long capillary tube is dipped in water. The water rises upto a height of 10 cm due to capillary action. If this experiment is conducted in a freely falling elevator, the length of the water column becomes :
10 cm
20 cm
30 cm
zero
An aeroplane gets its upward lift due to a phenomenon described by the :
Archimedes principle
Bernoulli's principle
Buoyancy principle
Pascal law
A wooden block is taken to the bottom of a deep, calm lake of water and then released. It rises up with a :
constant acceleration
decreasing aceleration
constant velocity
decreasing velocity
A.
constant acceleration
The wooden block moves upward with constant acceleration
Fb = Upthrust
A hollow conducting sphere is placed in an electric field produced by a point charge placed at P as shown in the figure. Let VA, VB, VC be the potentials at points A, B and C respectively. Then :
VC > VB
VB > Vc
VA > VB
VA = VC
Two spheres of radii R1 and R2 respectively are charged and joined by a wire. The ratio of the electric field of spheres is :
If a positive charge is shifted from a low potential region to a high potential region, the electric potential energy :
decreases
increases
remains the same
may increase or decrease