A pair of adult nitwits sit balanced on a teeter totter type device. One of them, whose mass is 54.2 kg, is 1.20 m from the point of balance. The other chowder-head is 2.25 m from the point of balance. What is the mass of the second person

The mass of the second person is 28.91 kg

Explanation:

Given;

mass of the first adult, m₁ = 54.2 kg

distance of the first adult from the point of balance, x = 1.20 m

mass of the second adult, = m₂

distance of the second adult from the point of balance, y = 2.25 m

Taking moment about the point of balance, we will have

m₁x = m₂y

54.2 x 1.2 = 2.25y

2.25y = 65.04

y = 65.04/2.25

y = 28.91 kg

Therefore, the mass of the second person is 28.91 kg

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.

e/c, where e is its total energy