Afreight train car with a mass of 1.2 _ 104 kilograms, travelling with a velocity of 23 meters/second, collides with a stationary freight train car of equal mass. what is the momentum of the system after the collision?
a. 1.2 × 105 kilogram meters/second
b. 1.4 × 105 kilogram meters/second
c. 2.4 × 104 kilogram meters/second
d. 2.8 × 105 kilogram meters/second

Jessie ran 5000 meters from the cops and an average speed of 6 meters / second before he got caught . how long did he run?

The ratio of lift to drag l/d for a wing or airfoil is an important aerodynamic parameter, indeed, it is a direct measure of the aerodynamic efficiency of the wing. if a wing is pitched through a range of angle of attack, l/d first increases, then goes through a maximum, and then decreases. consider an infinite wing with an naca 2412 airfoil. estimate the maximum value of l/d. assume that the reynolds number is 9x10^6.

An open cart is moving along a straight frictionless horizontal track. when rain starts falling vertically into the cart, what happens to the speed of the cart?