Question

Q4. A student places four identical beakers on a bench. What happens to the force on
the ground and what happens to the pressure on the ground?
A
B
C
150 cm
of salt
water
100 cm
of salt
water
150 cm
of pure
water
100 cm
of pure
water
Two beakers contain salt water of density 1.1 g/cm3 and two beakers contain pure
water of density 1.0 g/cm3. Which beaker exerts the greatest pressure on the bench?
Q5. The diagram shows a colid bi​

Answer 1

Given that,

A student places four identical beakers on a bench.

Volume of salt water in beaker A = 150 cm³

Volume of salt water in beaker B = 100 cm³

Volume of pure water in beaker C = 150 cm³

Volume of pure water in beaker D = 100 cm³

Density of salt water = 1.1 g/cm³

Density of pure water = 1.0 g/cm³

Force :

Force is equal to the mass and acceleration due to gravity.

In mathematically form,

$F=mg$

Where, m = mass

g = acceleration due to gravity

Pressure :

Pressure is equal to the force divided by area.

In mathematically form,

$P=\dfrac{F}{A}$

Where, F = force

A = area

We need to find the force on the surface on a bench

Using formula of force

$F = mg$

$F=\rho Vg$

Where, $\rho$ = density

V = volume

g = acceleration due to gravity

According to definition of force,

Whose is the density and volume more then his force will also be more on surface.

So, we can say that when the force will be more then the pressure will also be more.

We need to find which beaker exerts greatest pressure on the bench

Using pressure formula

$P=\dfrac{F}{A}$

$P=\dfrac{mg\times l}{A\times l}$

$P=\dfrac{\rho V\times g l}{V}$

$P=\rho gl$

Whose the density will be greater, his pressure will also be greater.

So, beaker A exert the greatest pressure on the bench

Hence, Beaker A exerts the greatest pressure on the bench.