


Large thrusts that cancel 


Smal thrusts that cancel 
The bottom arrow (dark red) is the initial velocity at the origin.
Questions:
The two fans cancel each other, so the net total force on the fancart is zero. If the cart is given an initial push (initial velocity) describe its subsequent motion.
Try all six combinations in the above table. Two entries are not very interesting. Explain – based on Newton II.
Explain the results for initial velocity nonzero. Does the cart stop, continue with the constant initial velocity, or accelerate?
Explain the results based on Newton II.
Suppose a parachute is falling with constant velocity. What is the total force (gravity and friction) on the parachute when it is falling with constant velocity? Remember Newton II.
End of midweek assignment. Please email discussions to dcollins@warrenwilson.edu
Physlets written by Wolgang Christian and Mario Belloni of Davidson College.
Javascript by Donald Collins of Warren Wilson College.