a 230 kg steel crate is being pushed along a cement floor. the force of friction is 480 n to the left and the applied force is 1860 n to the right. what is the normal force?
a.) 480 n down
b.) 480 n up
c.) 2300 n down
d.) 2300 n up

The correct answer is

D.) 2300 N up

In fact, the normal force is the reaction force exerted by the surface on the object, perpendicular to the surface itself, equal and opposite to the weight of the object.

Therfore, the magnitude of the normal force is equal to the weight of the object:

And since the weight is downward, the normal force is upward.

from 1609, galileo galilei used the recently invented telescope to observe the sun, moon and planets. he saw the mountains and craters of the moon, and for the first time revealed the planets to be worlds in their own right. galileo also provided strong observational evidence that planets orbited the sun.

his discoveries about the moon, jupiter's moons, venus, and sunspots supported the idea that the sun - not the earth - was the center of the universe, as was commonly believed at the time.galileo turned his gaze toward venus, the brightest celestial object in the sky - other than the sun and the moon.

massxgravity x heght=weightxheight= pe

4900=490xh

h=10