6. When an object is immersed in a liquid at rest, why is the net force on the object in the horizontal direction equal to zero? 7. When water freezes , it expands by about 9.0% What pressure increase would occur inside your automobile engine block if the water in it froze? (The bulk modulus of ice is 2.0times 10^9N/m^2)

6. When an object is immersed in a liquid at rest, the net force on the object in the horizontal direction is equal to zero because the liquid exerts an equal and opposite force on the object in all directions. This is due to the principle of buoyancy, which states that the upward force exerted by the liquid on the object is equal to the weight of the liquid displaced by the object. Since the forces in the horizontal direction cancel each other out, the net force on the object in the horizontal direction is zero.<br /><br />7. To calculate the pressure increase that would occur inside your automobile engine block if the water in it froze, we can use the formula for bulk modulus:<br /><br />Bulk Modulus (B) = (Pressure Increase) / (Volume Change)<br /><br />Given that the bulk modulus of ice is 2.0 x 10^9 N/m^2 and the volume change is 9.0% (or 0.09), we can rearrange the formula to solve for the pressure increase:<br /><br />Pressure Increase = Bulk Modulus x Volume Change<br /><br />Substituting the given values:<br /><br />Pressure Increase = (2.0 x 10^9 N/m^2) x (0.09)<br /><br />Pressure Increase = 1.8 x 10^8 N/m^2<br /><br />Therefore, the pressure increase that would occur inside your automobile engine block if the water in it froze would be 1.8 x 10^8 N/m^2.