p +p does not equal 0

You are asked to design a rollercoaster. It will have ten attached cars, each of which will have a mass of 500 kg and carry six people with average mass of 70.0 kg. You want to design a vertical circular loop with a radius of 55.0 m. The centre of the circle would have a height of 71.0 m above the ground.

how to write a source analysis 

“On the Rainy River" To what degree can an individual’s choices and actions influence the direction of his

or her life?

How do you express a major axis with a length of 2.992x10¹¹m in AU?

a roller coaster car filled with passengers has a mass of 4.80 kg. what speed must it have at the top of the 7.5 m tall circular loop so the car doesn't fall off?

How do you calculate how dense the Earth is? I keep trying but I get 3.51*10¹⁰kg/m³. I don't know how or where I'm going wrong.

A toboggan is resting in the snow.

What two (equal in magnitude and opposite in direction) forces is the scale measuring when you start to pull on the toboggan but it remains stationary? Be specific.

Mass of Pecan: 1.47g

Mass of H2O: 50g

Initial temperature of water: 23°C

Final temperature of water: 59°C

Calculate the quantity of energy produced per gram of fuel (nut) burned.

What does this text suggest to you about the forces that inhibit or encourage an individual’s actions?