Answer:
Explanation:
angular acceleration α = 5 rad /s ²
θ = 1/2 α t² , θ is angle of rotation , t is time .
= .5 x 5 x 4²
= 40 rad .
θ = l / r , θ is angle formed , l is length unwound , r is radius o wheel .
l = θ x r
= 40 x .1
= 4 m .
Answer:
A) and B) are correct.
Explanation:
If the object is at rest, it means that no net force is exerted on it.
As the object experiences a downward gravitational force from Earth, in order to be at rest, it must experience an upward force with the same magnitude as the gravitational force on the object.
This force is supplied by the normal force, which can adopt any value in order to meet the condition imposed by Newton´s 2nd Law, and is always perpendicular to the surface on which the object is placed (in this case, the ground).
At a molecular level, this normal force is supplied by the bonded molecules of the ground that behave like small springs being compressed by the molecules of the object, exerting an upward restoring force upward on them.
So, the statements A) and B) are true.
Answer:
Dryer sheets stop static cling by absorbing static electricity formed by different fabrics during your dryer cycle. The fabric softeners that coat dryer sheets are positively charged ions to balance the electrons and ions that cause static cling, leaving you with soft clothes without the static.
Explanation:
The energy of a single photon is given by:

where
E is the energy
h is the Planck constant
f is the frequency of the light
The light in our problem has a frequency

, so the energy of each photon of that light is: