Consider a water tank as shown in the figure. It's cross-sectional area is 0.4 m². The tank has an opening B near the bottom whose cross-section area is 1 cm². A load of 24 kg is applied on the water at the top when the height of the water level is 40 cm above the bottom, the velocity of water coming out the opening B is v ms^-1.

The value of v, to the nearest integer, is ___________. [Take value of g to be 10 ms^-2]

The radius of a sphere is measured to be (7.50 $$\pm$$ 0.85) cm. Suppose the percentage error in its volume is x.

The value of x, to the nearest x, is __________.

The projectile motion of a particle of mass 5 g is shown in the figure.


The initial velocity of the particle is $$5\sqrt 2 $$ ms^-1 and the air resistance is assumed to be negligible. The magnitude of the change in momentum between the points A and B is x $$\times$$ 10^-2 kgms^-1. The value of x, to the nearest integer, is __________.

An infinite number of point charges, each carrying 1 $$\mu$$C charge, are placed along the y-axis at y = 1 m, 2 m, 4 m, 8 m ...............

The total force on a 1C point charge, placed at the origin, is x $$\times$$ 10³ N.

The value of x, to the nearest integer, is __________. [Take $${1 \over {4\pi {\varepsilon _0}}} = 9 \times {10^9}$$ Nm²/C²]