The basic barometer can be used to measure the height of a building. if the barometric readings at the top and at the bottom of a building are 665 and 695 mmhg, respectively, determine the height of the building. take the densities of air and mercury to be 1.18 kg/m3 and 13,600 kg/m3, respectively. (round the answer to the nearest whole number.)

The height of the building is 346 m.

Explanation:

Using the pressure formula that relate atmosphera pressure and manometric pressure like: we can find delta of height and delta of pressure. So , knowing that 1(mmHg) is equal to 133 Pa we can do the convertion to 4000 Pa, because the units of Pascal is Newton/(metre^2). Then we solve the formula to get the height: so we get: , now we can .

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.