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?

Jamal is pulling a 4,900 N box with a force of 500 N. Jakob is pulling in the opposite direction with a force of 350 N. How fast will the box be moving after 5 seconds?

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 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?

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 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?

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?

A 1000-kg car moving north at 100km/h brakes to a stop in 50m. What are the magnitude and direction of the force?

 

A car accelerates from 10 m/s to 50 m/s while traveling 400 m. The mass of the car is 1500 kg. What force was applied to the car?

Four passengers with mass 85 kg apiece are added to the problem above, how much would that change the force required?

A 5.0 kg missle is projected from rest to a speed of 4.5 x 10³ m/s. How much time is required to do this by a net force of 5.3 x 10⁵ N?