Answer:
a
[tex]W_s = 8[/tex]
b
[tex]P = 594 000 \ Pa[/tex]
Explanation:
Considering question a
From the question we are told that
The weight of the object in air is [tex]W_1 = 7.84 \ N[/tex]
The weight of the object in water is [tex]W_2 = 6.86\ N[/tex]
Generally the specific gravity of the object is mathematically represented as
[tex]W_s = \frac{W_1 }{W_1 - W_2 }[/tex]
=> [tex]W_s = \frac{7.84}{7.84 -6.86 }[/tex]
=> [tex]W_s = 8[/tex]
Considering question b
From the question we are told that
The pressure required is [tex]P_r = 300 \ kPa = 300 *10^{3} \ Pa[/tex]
The height is [tex]h = 30.0 \ m[/tex]
Generally the pressure require to get the water to the given height is mathematically represented as
[tex]P_h = \rho * g * h[/tex]
Here [tex]\rho[/tex] is the density of water with value [tex]\rho = 1000 \ kg / m^3[/tex]
So
[tex]P_h = 1000 * 9.8 * 30[/tex]
=> [tex]P_h = 294000 \ Pa[/tex]
Generally the pressure require to pump the water to the given height at the require pressure is mathematically represented as
[tex]P = P_h + P_r[/tex]
=> [tex]P = 294000 + 300*10^{3}[/tex]
=> [tex]P = 594 000 \ Pa[/tex]
