Answer:

Explanation:
let the ladder is of mass "m" and standing at an angle with the ground
So here by horizontal force balance we will have

by vertical force balance we have

now by torque balance about contact point on ground we will have

so we will have

now from first equation we have


Dark matter may explain <span>unexpected orbital velocities of stars in galaxies.</span>
Answer:
8) d
9) c
<em>Hope this helps! :)</em>
Answer:
If one charged object is positive, and the other charged object is negative, then the two objects will attract each other. If both objects are positive, the objects will repeal each other. If both objects are negative, the objects will also repeal each other.
When skeletal muscles contract, bones move. But how do muscles make your bones move? A voluntary muscle usually works across a joint. It is attached to both the bones on either side of the joint by strong cords called tendons. A tendon is a tough band of connective tissue that connects a muscle to a bone. Tendons are similar to ligaments, except that ligaments join bones to each other. Muscles move the body by contracting against the skeleton. When muscles contract, they get shorter. By contracting, muscles pull on bones and allow the body to move.
Hope this will you to understand the movement of the skeletal muscles