Explanation:
Many would know it as a reaction force. Reaction force is the force by the surface on the object perpendicular to it's motion. So if we apply force on the sliding block perpendicular to it's direction of motion, friction will increase. ... That force is proportional to the velocity with which it is moving.
It should be the second one
Answer:
a kind of radiation including visible light, radio waves, gamma rays, and X-rays, in which electric and magnetic fields vary simultaneously
a. 13.23 N
b. 13.2
What you need to do is use this equation:
(m1 + m2) x g
<u><em>hope it helps!</em></u>