Howard is standing in the middle of a skating rink (we'll assume no friction), and his four friends Alice, Bernie, Christopher, and David approach him from each of the four compass directions - north, east, south, and west, respectively.

Alice pushes on Howard with a force of x + 20 Newtons. Bernie pushes on him with a force of 2x + y Newtons. Christopher pushes on him with a force of 2x - y Newtons, and David pushes with a force of 5y Newtons.

Howard, though being pushed from all directions, does not move. Calculate the forces being applied in all four directions.

A mass, m₁, accelerates at 3 m/s² when a force, F, is applied. A second mass, m₂, accelerates at 1.0 m/s² when F is applied to it.

1. Find the value of the ratio m₁/m₂.
2. Find the acceleration of the combined mass ( m₁ + m₂) under the action of the force, F.
    

A 50 slug car can accelerate from 0 to 50 ft/s while traveling 1000 feet. The car then stops, and a passenger gets in. Now the car can accelerate from 0 to 50 ft/s while traveling 1050 feet. What is the weight of the passenger?

After Luke Skywalker got his X-Wing fighter out of the swamp on Dagobah, he wanted to make it fly. The mass of the ship is 5,000 kg. Luke applies (using the force) an upward force of x Newtons. Yoda, who doesn't want Luke to get too confident, applies a downward force which is two-thirds of Luke's force.

Luke's Skywalker X-Wing fighter lifts off to a height of 2 km in 5 seconds. How much force did Luke apply?

If a force accelerates 4.5 kg at 40 m/s², that same force would accelerate 18 kg by how much?

I would like to get from City A to City B, which are 200 miles apart, in the shortest amount of time, given the stipulation that I don't want to experience a force more than 4 times the force of gravity. What is shortest amount of time this trip can take?

A hockey stick travels backward 11.0 cm while intercepting a 0.140 kg puck. How much force did the stick exert on the puck to bring the puck from 35.0 m/s to rest?

1.A horizontal force of 10N is applied to a 30 kg cart on a level floor. 

1. How far will it move in 3.0s, starting from rest? Ignore friction. 
2. How far will it move in 3.0s if 30N of groceries is added to the cart first?

An elevator has a mass of 2,000 kg.  An upward force of 21,000 Newtons is applied to the elevator. The elevator travels up 50 floors, and each floor is 2.5 meters tall, with a 20 centimeter gap between floors. How long does it take the elevator to arrive, and at what speed will it be traveling?

A 6000 kg tractor rests on a flatbed, held in place by chains. The chains provide a maximum horizontal force of 8000 N. When the flatbed is traveling 20 m/s, what is the minimum stopping distance if the chains are not to break?