Answer:
About 428 N
Step-by-step explanation:
Weight = 1,500 * 9.8 = 14,700 N
Density = Mass ÷ Volume
1,030 = 1,500 ÷ V
V = 1,500 ÷ 1,030 = 1.46 m^3.
Buoyant force = Density * g * V
Buoyant force = 1,000 * 9.8 * (1,500 ÷ 1,030)
Buoyant force = 9,800 * (1,500 ÷ 1,030) = 14,272 N.
Net force = 14,700 – [(9,800 * (1,500 ÷ 1,030)]
We want to find the approximate value of the upward normal force on a hippo that is completely submerged and standing on the bottom of the lake.
The total normal force is 14,700 N
We define the normal force as the force that a surface or material does when something wants to move through it. So, if the hippo stands on the ground, the ground does a normal force against the hippo so the hippo does not fall through the ground.
In this case, the normal force must be equal to the hippo's weight, so the vertical net force on the hippo is equal to zero.
But in the water, the normal force done by the ground will be different, this is because the fluid causes a buoyant force (this force depends on the amount of fluid displaced)
But by definition, the buoyant force is a normal force, it is a contact force that the water does against the hippo. (think that as the hippo enters in the water, the water applies this force to resist the hippo).
So there are two normal forces on the completely submerged hippo, the one done by the water, and the one done by the lake's floor.
And the hippo is standing there, so the net force must be zero, meaning that the sum of these two normal forces must be, in magnitude, equal to the hippo's weight, which is:
W = -9.8m/s^2*1500kg = -14,700 N
(the negative sign is because the weight pulls the hippo downwards).
Then the total normal force must be equal to 14,700 N so the net force is zero and the hippo can stand still on the bottom of the lake.
If you want to learn more, you can read:
https://brainly.com/question/18799790
