1
JEE Main 2021 (Online) 20th July Morning Shift
+4
-1
The value of tension in a long thin metal wire has been changed from T1 to T2. The lengths of the metal wire at two different values of tension T1 and T2 are l1 and l2 respectively. The actual length of the metal wire is :
A
$${{{l_1} + {l_2}} \over 2}$$
B
$$\sqrt {{T_1}{T_2}{l_1}{l_2}}$$
C
$${{{T_1}{l_2} - {T_2}{l_1}} \over {{T_1} - {T_2}}}$$
D
$${{{T_1}{l_1} - {T_2}{l_2}} \over {{T_1} - {T_2}}}$$
2
JEE Main 2021 (Online) 17th March Evening Shift
+4
-1
An object is located at 2 km beneath the surface of the water. If the fractional compression $${{\Delta V} \over V}$$ is 1.36%, the ratio of hydraulic stress to the corresponding hydraulic strain will be ____________. [Given : density of water is 1000 kgm$$-$$3 and g = 9.8 ms$$-$$2]
A
1.44 $$\times$$ 107 Nm$$-$$2
B
1.44 $$\times$$ 109 Nm$$-$$2
C
1.96 $$\times$$ 107 Nm$$-$$2
D
2.26 $$\times$$ 109 Nm$$-$$2
3
JEE Main 2021 (Online) 17th March Morning Shift
+4
-1
When two soap bubbles of radii a and b (b > a) coalesce, the radius of curvature of common surface is :
A
$${{b - a} \over {ab}}$$
B
$${{a + b} \over {ab}}$$
C
$${{ab} \over {a + b}}$$
D
$${{ab} \over {b - a}}$$
4
JEE Main 2021 (Online) 16th March Evening Shift
+4
-1
What will be the nature of flow of water from a circular tap, when its flow rate increased from 0.18 L/min to 0.48 L/min? The radius of the tap and viscosity of water are 0.5 cm and 10$$-$$3 Pa s, respectively. (Density of water : 103 kg/m3)
A
B
C
Remains turbulent flow
D