can u give me an example in which the normal force is zero?

Answer 1

considering light quantum as particles, when they strike on any surface the normal force will be zero because light particles are massless.

Answer 2

The normal force is zero whenever the perpendicular force between an object and the surface it's touching is zero. (Note that the surface does not need to be horizontal.) kuiperbelt2003 provided the easiest example. Another example is when a car or roller coaster goes upside down around a loop-de-loop at just the right speed. If you adjust the speed correctly, you can get the normal force (track pushing down against car) to be zero at the moment the car is upside down. (Note: in real roller coasters, this is dangerous, so they go fast enough to keep the normal force at a nonzero value.)

Answer 3

What is confusing about your question is the statement "box being pulled at an angle of 36 degrees". This could mean that the box is on a 36º slope, or that the box is on a horizontal surface and the force acts at 36º above or below horizontal, However, on a horizontal table, Fn has no horizontal component because that is what "normal" means: right angles to the horizontal. The force of gravity is also at right angles to the horizontal; the force of gravity is a normal force and has no horizontal component on a horizontal table.

Answer 4

any time an object has a force acting upon it and it is not against a surface that will cause an equal but opposite reaction.

Example - a free falling skydiver => gravity from the earth acts on him, and there is no normal force.

Answer 5

When you move the object away from a gravitational field.

i.e. Far, far, in the deepest reaches of space (minimal gravitational field), you can minimize or remove the effect of the mass / weight generating the normal force.

Note:

You can also do the same by (theoretically) removing any source of friction. A normal force (F) due to friction (mu) and the weight of an object (N) is calculated by:

F = mu*N

If you remove friction (i.e. if you have a very, very, fine surface you can at least minimized the effects), your normal force will be reduced (can be minimized to zero).

Answer 6

If you can cause the action of gravity to be perfectly parallel between two objects, there will be no normal force. The only other way to get rid of a normal force is to have no gravity.(as in deep space)

Answer 7

if you place on object against a vertical wall and release it to let it fall, there is no normal force between the wall and the object; the normal force is the force pressing the two surfaces together, in this case, the weight of the object acts vertically (straight down), and there is no component of weight acting on the surface, so there is no normal force between the object and surface