Apparent forces in circular motion

[lokobreed]

Homework Statement

The passengers in a roller coaster car feel 50% havier than their true weight as the car goes through a dip with a 30 m radius of curvature. What is the cars speed at the bottom of the dip?

Homework Equations

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The Attempt at a Solution

I understand that there are two forces affecting the rollercoaster car - the normal force and the weight (mass x gravity)... Also since they feel 50% heavier the normal force must be greater than the weight. so n (normal force) > w (mass x gravity) thus the n = 1.50w.

So sum of force = n - w = 1.50 w - w after this I am completely lost... can anyone help please!

 

[PhanthomJay]

The net force you have correctly calculated as 0.5w is the centripetal force. Calculate v using the centripetal force equation .

 

[ideasrule]

Draw a free-body diagram of the roller coaster, label all forces, and write out Newton's second law for the vertical direction. What's the acceleration?

 

[lokobreed]

thank you
I got 12m/s

 

[PhanthomJay]

yes...looks good.