Ball and Hoop

The video tutorial explores the effects of heating and cooling on a brass ball and hoop. Initially, the ball fits through the hoop at room temperature. When heated, the ball expands due to increased kinetic energy, preventing it from passing through the hoop. Upon cooling, the ball contracts and fits through again. This demonstrates thermal expansion and contraction. The tutorial also discusses real-world implications, such as thermal expansion joints in bridges to prevent structural damage.

What materials are required for the experiment described in the video?

• A copper ball, a copper hoop, and a heat source

• A brass ball, a brass hoop, and a heat source

• A plastic ball, a plastic hoop, and a heat source

• A steel ball, a steel hoop, and a heat source

What happens to the brass ball when it is heated for approximately 2 minutes?

• It shrinks and passes through the hoop easily

• It melts completely

• It changes color but remains the same size

• It expands and no longer fits through the hoop

What is the main reason for the brass ball not fitting through the hoop after heating?

• The hoop shrinks

• The hoop expands

• The ball expands

• The ball changes shape

What is the term used to describe the increase in size of the brass ball when heated?

• Thermal compression

• Thermal reduction

• Thermal expansion

• Thermal contraction

What happens to the brass ball as it cools down after being heated?

• It expands further

• It remains the same size

• It changes color

• It contracts and becomes smaller

Why are thermal expansion joints used in bridges?

• To reduce the cost of construction

• To increase the weight of the bridge

• To make the bridge more aesthetically pleasing

• To allow sections of the bridge to expand without causing damage

What is the effect of thermal expansion on metal structures in hotter climates?

• It has no effect on the structures

• It can lead to damage such as cracking and buckling

• It causes the structures to become more flexible

• It strengthens the structures