Normal Force and Centripetal Motion

The video tutorial explains how to calculate the normal force on a 5 kg box moving at 15 m/s at two points, A and B. It discusses the forces involved, including weight and centripetal force, and how they affect the normal force at each point. At point A, the normal force is the sum of the centripetal and weight forces, while at point B, it is the difference. The tutorial also covers the concept of maximum speed at point B to maintain contact with the road and the minimum speed required for a roller coaster to keep passengers safe when upside down. Key calculations and concepts are demonstrated throughout.

What is the primary reason the normal force is greater at point A compared to point B?

• The box is heavier at point A.

• The ground at point A is steeper.

• The box needs to turn upward at point A.

• The speed of the box is higher at point A.

How is the normal force at point A calculated?

• By dividing the centripetal force by the weight force.

• By adding the centripetal force and the weight force.

• By subtracting the weight force from the centripetal force.

• By multiplying the centripetal force with the weight force.

What happens to the normal force at point B if the box moves too fast?

• It becomes negative, indicating loss of contact.

• It increases, ensuring more stability.

• It remains constant regardless of speed.

• It doubles, providing extra support.

What is the condition for the maximum speed at which the box can maintain contact with the road at point B?

• The normal force is equal to the centripetal force.

• The normal force is zero.

• The weight force is zero.

• The centripetal force is zero.

How is the maximum speed at point B calculated?

• By dividing the weight force by the radius.

• By taking the square root of the product of radius and gravitational acceleration.

• By multiplying the centripetal force by the radius.

• By adding the weight force and centripetal force.

What is the minimum speed required for a roller coaster to prevent passengers from falling out when upside down?

• The speed must be double the square root of rg.

• The speed must be greater than the square root of rg.

• The speed must be equal to the square root of rg.

• The speed must be less than the square root of rg.

In the roller coaster problem, what direction does the normal force point when the coaster is upside down?

• Away from the center of the circle

• Towards the center of the circle

• Negative y direction

• Positive y direction

What happens if the roller coaster moves too slowly at the top of the loop?

• The centripetal force exceeds the weight force.

• The roller coaster falls down.

• The normal force becomes positive.

• The normal force becomes zero.

What is the relationship between the centripetal force and weight force for the roller coaster at the top of the loop?

• Centripetal force is greater than weight force.

• Weight force is greater than centripetal force.

• They are equal.

• They are unrelated.

What is the significance of the square root of rg in the context of the roller coaster problem?

• It represents the maximum speed.

• It represents the minimum speed.

• It represents the average speed.

• It represents the constant speed.