If you exert a force on an object in a positive direction,can the object be moving with a velocity in the negative direction.Explain your reasoning.

Two objects, A and B, are in contact with each other on a frictionless surface. Object A has a mass of 5 kg, while object B has a mass of 3 kg. Object A exerts a force of 20 Newtons on object B. According to the Third Law of Motion, what is the magnitude of the force exerted by object B on object A? A) 8 N   B) 12 N   C) 15 N   D) 20 N

Two different experiments are performed.  IN the first experiment constant force is applied to a hydrogen ion. In the second experiment, the same constant force is applied to an ion 9 times the mass of hydrogen. What is the ratio of the time interval for each ion as it travels from A to B.

An object of mass m is at rest on a smooth horizontal surface. It is pulled by a variable force F = kt, where t is the time. The force makes and angle a with the horizontal. a) find an expression for the speed of the object when it starts to lift-off the surface. b) find an expression for the distance travelled until it starts to lift-off the surface.

A 5.0 kg object has a set of three forces acting on it, as shown in the diagram. At t = 0, the object is located at the origin and is at rest.                  a)  Use Newton’s second law to find the acceleration of the object. Give both the magnitude and the direction (relative to the +x axis).               b)  What is the velocity of the object at t = 7.50 seconds? Give both the magnitude and the direction (relative to the +x axis).               c)  How far is the object from the origin at t = 7.50 seconds?

Topic:  You find yourself trapped in the middle of a large frozen lake. Assume the ice has no friction. All you have on your is warm winter clothing and no way to call/signal for help. You can just barely see the shore in the distance. Use your physics knowledge of Newton's laws to help get you off the lake. Explain your reasoning.