Strictly speaking, you weigh a tiny bit less when you are in the lobby of a massive skyscraper than you do at home. Why is this so?

In the lobby of a skyscraper,there is a lot of mass above you, at relatively close range. This exerts an upward gravitational force on you that opposes the downward gravitational pull of the Earth below.The net result is a lwer value of "g".

A pendulum clock would move slightly more slowly in that lobby, and gradually lose time.

When you weigh yourself in the lobby of a massive skyscraper, you may find that you weigh a tiny bit less compared to when you weigh yourself at home. This phenomenon can be attributed to a concept known as gravitational force.

Gravity is the force that attracts objects towards each other. The strength of gravity depends on the mass of the objects and their distance apart. The larger the mass of an object, the greater its gravitational pull.

In the case of a massive skyscraper, it consists of a massive amount of materials, such as concrete and steel. Due to its enormous mass, it exerts a gravitational force on objects within its vicinity, including you. This gravitational force effectively pulls you towards the center of the skyscraper.

When you stand in the lobby of a skyscraper, you are actually slightly farther from the Earth's center compared to when you are at home. As a result, the gravitational pull acting on you in the skyscraper is slightly weaker than the gravity experienced at home. This causes a minute reduction in your weight while in the skyscraper lobby.

However, it's important to note that this weight difference is extremely small and would require highly precise instruments to detect. For practical purposes, the weight difference experienced in a skyscraper would generally be negligible and not noticeable to the average person.