Numerical examples on Kinematics

A box of mass M is sitting at rest on an incline at an angle of ! as shown above. Which of the following is true: 1) Gravity and the normal force from the surface can keep the block stationary. 2) An additional force, which must point up along the incline, is needed. 3) An additional force, which must point vertically up, is needed. 4) An additional force which must point the to the right is needed. 5) An additional force, which must have a component pointing to the right, is needed. 6) An additional force is needed but it can be in any direction provided it is the correct magnitude. 7) An additional force, whose magnitude and direction must both be specific values, is needed. A bird is initially standing inside a closed box that is resting on a scale. The bird jumps into the air and begins flying around the box staying at a constant height. Assume that the scale can adjust instantaneously to any change in applied force. While the bird is in the air inside the box, does the scale: 1) Increase its reading from when the bird is standing on the floor? 2) Decrease its reading from when the bird is standing on the floor? 3) Give the same reading as when the bird is standing on the floor? 4) Not enough information given. A person is initially standing inside a closed box that is resting on a scale. The person jumps in the air. Assume that the scale can adjust instantaneously to any change in force applied to it. While the person is in the air inside the box, does the scale: 1) Increase its reading from when the person is standing on the floor? 2) Decrease its reading from when the person is standing on the floor? 3) Give the same reading as when the person is standing on the floor? 4) Not enough information given.