Q20)
Q21)
Q21) A brick weighing 20 N has dimensions of 20 cm × 10 cm × 8 cm. Calculate the pressure exerted by the brick on the surface when it rests on:
a) The 20 cm × 10 cm face ?
b) The 20 cm × 8 cm face ?
Q22)
Q22) A swimming pool is 25 m long, 10 m wide, and has a uniform depth of 2.5 m. If the density of water is 1000 kg/m³,
calculate: a) The pressure at the bottom of the pool ?
b) The total force exerted by the water on the bottom of the pool ?
Q23)
Q23) A diver is exploring a lake at a depth of 18 meters. The density of freshwater is 1000 kg/m³, and atmospheric pressure is 101,300 Pa. Calculate: a) The gauge pressure at this depth?
b) The absolute pressure at this depth?
c) The force exerted on a rectangular diving mask with dimensions 16 cm × 8 cm at this depth?
Q24)
Q24) An eardrum has a diameter of 7.5 mm. The eardrum can be damaged if the force on it increases by 1.2 N above the force from atmospheric pressure. If the density of seawater is 1025 kg/m³,
calculate: a) the area of the eardrum?
b) the additional pressure that would cause damage ?
c) the ocean depth at which this pressure would be reached?
