1
JEE Main 2020 (Online) 5th September Evening Slot
+4
-1
In an experiment to verify Stokes law, a small spherical ball of radius r and density $$\rho$$ falls under gravity through a distance h in air before entering a tank of water. If the terminal velocity of the ball inside water is same as its velocity just before entering the water surface, then the value of h is proportional to :
(ignore viscosity of air)
A
r
B
r4
C
r3
D
r2
2
JEE Main 2020 (Online) 5th September Morning Slot
+4
-1
A hollow spherical shell at outer radius R floats just submerged under the water surface. The inner radius of the shell is r. If the specific gravity of the shell material is $${{27} \over 8}$$ w.r.t water, the value of r is :
A
$${{2} \over 3}$$R
B
$${{4} \over 9}$$R
C
$${{1} \over 3}$$R
D
$${{8} \over 9}$$R
3
JEE Main 2020 (Online) 4th September Evening Slot
+4
-1
A cube of metal is subjected to a hydrostatic pressure of 4 GPa. The percentage change in the length of the side of the cube is close to :
(Given bulk modulus of metal, B = 8 $$\times$$ 1010 Pa)
A
0.6
B
20
C
1.67
D
5
4
JEE Main 2020 (Online) 4th September Evening Slot
+4
-1
Two identical cylindrical vessels are kept on the ground and each contain the same liquid of density d. The area of the base of both vessels is S but the height of liquid in one vessel is x1 and in the other, x2 . When both cylinders are connected through a pipe of negligible volume very close to the bottom, the liquid flows from one vessel to the other until it comes to equilibrium at a new height. The change in energy of the system in the process is:
A
gdS(x2 + x1)2
B
gdS$$\left( {x_2^2 + x_1^2} \right)$$
C
$${1 \over 4}gdS{\left( {{x_2} - {x_1}} \right)^2}$$
D
$${3 \over 4}gdS{\left( {{x_2} - {x_1}} \right)^2}$$
EXAM MAP
Medical
NEET