Forces in Two Dimensions - Mission F2D2 Detailed Help

A box is being accelerated across a level surface. A force is being applied to the box in an upward and a rightward direction (as shown). This force makes an angle of 30 degrees with the horizontal. If the angle at which the force is exerted is increased to 45 degrees, then the force of gravity would ...

Changing the angle that the applied force makes with the horizontal will change a lot of things. First, as the angle is changed, the x- and y- components of the force will change. This will cause a change in the normal force that in turn causes a change in the friction force. Since the horizontal forces have changed, the net force and acceleration will change. But what about the force of gravity? Don't be fooled! The force of gravity or weight of an object is dependent upon the mass of the object and the location of the object in the universe (Earth's surface, moon, Jupiter, etc.). Changing the angle at which the applied force is exerted will not change either of these variables and thus the weight is unaffected.

The force of gravity (Fgrav) acting upon an object can be determined from the mass of an object using the equation:
Fgrav= mass • g
where g is the acceleration caused by gravity alone. The value of g on Earth is 9.8 m/s/s.