Question

A high school physics student is sitting in a seat reading this question. The magnitude of the force with which the seat is pushing up on the student to support him is closest to what?

Answer 1

Answer:

Force due to seat must be equal to the Weight of the student

Explanation:

As we know that the student is sitting on the seat at rest

So here we can say that at this position the student must be at equilibrium position

so we can write force equation for this position of student

vertically downward the net force is due to his/ her weight which is given as

$W = mg$

now this weight of the student is counter balanced by the the normal force due to seat which is in opposite direction

Now for equilibrium position of the object we will have

$F_n = mg$

so the seat will push the student upwards by force which is equal to the weight.

Answer 2

The force pushing down  is the force of Gravity. On a chair it is in perfect balance with the force pushing up (the normal force)
 

in terms of magnitude 
FN = FG = mg

the forces are in opposite direction

hope this helps