Answer:
P + C = W if in equilibrium?
P + C - W = 0; P + C = W
Explanation:
Action and reaction are equal and opposite according to newton's third law of motion. a force is that which tends to change a body's state of rest or uniform motion in a straight line, recall
P is the upward force the person exerts on the crate,
C is the vertical contact force exerted on the crate by the floor,
W is the weight of the crate
let the sum of upward forces be on the left hand side of the equation and the sum of downward forces on the right hand side.
P+C=W
P+C-W=0 if they are in equilibrium
the forces are related by the above.
First we have to calculate the time taken to travel the distance 30 m, is
.
Now from equation of motion,

Given,
.
As object starts from rest, so u = 0.
Substituting these values in above equation, we get
.
Thus, the acceleration is 
Answer:
the answer would be D. Yelling out in a cave and hearing your voice call back to you
Explanation:
The answer is 4 because N=1 and H3
The vertical force acts perpendicular to the horizontal motion and will not affect it since perpendicular components of motion are independent of each other. Thus, the projectile travels with a constant horizontal velocity and a downward vertical acceleration.