Answer:
a. It always points perpendicular to the contact surface.
Explanation:
"Normal" means perpendicular. Normal forces are always perpendicular to the contact surface.
Answer:D.Refractive Indez
Explanation:
It is usually expressed the other way: the ratio of the speed of light in a vacuum to the speed of light in a medium. In that case, it is called the "index of refraction".
<h2>
Answer: 12 s</h2>
Explanation:
The situation described here is parabolic movement. However, as we are told <u>the instrument is thrown upward</u> from the surface, we will only use the equations related to the Y axis.
In this sense, the main movement equation in the Y axis is:
(1)
Where:
is the instrument's final position
is the instrument's initial position
is the instrument's initial velocity
is the time the parabolic movement lasts
is the acceleration due to gravity at the surface of planet X.
As we know
and
when the object hits the ground, equation (1) is rewritten as:
(2)
Finding
:
(3)
(4)
(5)
Finally:

When Adam applies a ‘pull’ force on the pulley, there is an output force that the pulley lets out, directly pulling the object with it. We cannot always pull up objects with our bear hands, no matter how much force we apply. Which is why pulleys allow us to apply the force and pulleys do the work of pulling the objects for us, since work and force come hand in hand.