12. A body of mass 2kg and a Vol of 0.0005m³ is hung from a balance graduated in Newton . What would be the balance read when the body is in air ?
When it is fully immersed in water ?
When it is immersed in paraffin of of density 800kg?
How help me
W = weight = m g = 2 * about 10 m/s^2 = 20 Newtons
force up = volume * density * g = 0.0005 * 1000 kg/m^3 * 10 = 5 Newtons
now reads 20 - 5 = 15 N
Now you can do it for density = 800 instead of 1000
force up = volume * density * g = 0.0005 * 800 kg/m^3 * 15=6Newtons??
force up = volume * density * g = 0.0005 * 800 kg/m^3 * 10= 8 Newtons??
g is about 10, not 15
so now the scale reads 20 - 8 = 12 Newtons
sorry
force up = volume * density * g = 0.0005 * 800 kg/m^3 * 10= 4 Newtons??
g is about 10, not 15
so now the scale reads 20 - 4 = 16 Newtons
To find the balance read in each scenario, we need to consider the buoyant force acting on the body. The buoyant force is the upward force exerted on an object submerged in a fluid.
1. When the body is in the air:
In this case, the body is not submerged in any fluid, so there is no buoyant force acting on it. Therefore, the balance read will be equal to the weight of the body, which is given by the formula:
Weight = mass * gravitational acceleration
Weight = 2 kg * 9.8 m/s²
Weight = 19.6 N
So, the balance will read 19.6 Newtons when the body is in the air.
2. When the body is fully immersed in water:
When the body is completely submerged in water, it experiences a buoyant force equal to the weight of the water displaced by the body. The volume of the body is given as 0.0005 m³.
To find the weight of the water displaced, we use the formula:
Weight of water displaced = density of water * volume of water * gravitational acceleration
The density of water is approximately 1000 kg/m³, and the gravitational acceleration is 9.8 m/s². Therefore:
Weight of water displaced = 1000 kg/m³ * 0.0005 m³ * 9.8 m/s²
Weight of water displaced = 4.9 N
Since there is now an upward buoyant force acting on the body, the balance will read 4.9 Newtons less than the weight of the body in air. Therefore, the balance will read:
Balance read = Weight in air - Weight of water displaced
Balance read = 19.6 N - 4.9 N
Balance read = 14.7 N
So, the balance will read 14.7 Newtons when the body is fully immersed in water.
3. When the body is immersed in paraffin of density 800 kg/m³:
Using a similar approach as before, we can calculate the weight of paraffin displaced by the body. The density of paraffin is given as 800 kg/m³.
Weight of paraffin displaced = density of paraffin * volume of paraffin * gravitational acceleration
Weight of paraffin displaced = 800 kg/m³ * 0.0005 m³ * 9.8 m/s²
Weight of paraffin displaced = 3.92 N
Therefore, the balance will read:
Balance read = Weight in air - Weight of paraffin displaced
Balance read = 19.6 N - 3.92 N
Balance read = 15.68 N
So, the balance will read 15.68 Newtons when the body is immersed in paraffin of density 800 kg/m³.