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11 grade physics others

A hole is made at the bottom of a tank filled with water. If total pressure at the bottom of the tank is three atmosphere, the velocity of efflux at the bottom is (1 atm = 105 N m-2)

  • A. √400 m s-1
  • B. √200 m s-1
  • C. √600 m s-1
  • D. √500 m s-1

Profile image of Aniket Singh
10 Months agoGrade
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1 Answer

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ApprovedApproved Tutor Answer10 Months ago

To find the velocity of efflux from a hole at the bottom of a tank filled with water, we can use Torricelli's theorem. According to this principle, the velocity \( v \) of fluid flowing out of an orifice under the influence of gravity can be calculated using the formula:

Formula for Velocity of Efflux

The formula is given by:

v = √(2gh)

Where:

  • g = acceleration due to gravity (approximately 9.81 m/s²)
  • h = height of the fluid column above the hole

Calculating Pressure and Height

In this scenario, the total pressure at the bottom of the tank is given as three atmospheres. Since 1 atmosphere equals \( 10^5 \, \text{N/m}^2 \), we can convert this pressure:

Pressure = 3 atm = 3 × 10^5 N/m²

Using the hydrostatic pressure formula:

Pressure = ρgh

Where:

  • ρ = density of water (approximately \( 1000 \, \text{kg/m}^3 \))
  • h = height of the water column

Finding Height

Rearranging the formula to find height:

h = Pressure / (ρg)

Substituting the values:

h = (3 × 10^5) / (1000 × 9.81) ≈ 30.6 \, \text{m}

Calculating Velocity

Now, substituting \( h \) back into the velocity formula:

v = √(2gh) = √(2 × 9.81 × 30.6)

Calculating this gives:

v ≈ √600 \, \text{m/s}^2

Final Answer

The velocity of efflux at the bottom of the tank is approximately:

√600 m/s

Thus, the correct option is C. √600 m/s.