Calculate the normal force, n, acting on a rider in an elevator if his mass is m=72.1 kg and the acceleration due to gravity g= 9.8m/s^2. the elevator has constant velocity. a) 0 n
b) 406 n
c) 707 n
d) 1008 n

Normal force,   = 707 N

Given:

Mass of the rider, M = 72.1 kg

acceleration due ti gravity, g = 9.8 m/

Velocity of the elevator is constant

Solution:

Since, the elevator is moving with a constant velocity, therefore, the frame we are dealing with is an inertial frame and will not allow any pseudo force to act on it.

The Normal force, N will now be equal to the weight, W of the body which is the product of its mass and the acceleration acting on the body due to gravity and is given by:

= W =

putting the values in the above formula

=  

= 707 N (approx)

1/0.14nm = 10^10/1.4 a lot

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.