When an object is free-falling, no other force is acting upon it but the gravitational force. Because of this, the equations of motion are simplified. We can determine first the initial velocity:
v = √2gy = √2(9.81)(4.9) = 9.805 m/s
Then, we use this to the equation below:
y = vt + 1/2*at²
y = (9.805)(0.5) + 1/2(9.81)(0.5)²
y = 6.13 m
Answer:
Direction 1: Force is Non-zero and Not- constant
Direction 2: Force is Non-zero but constant
Explanation:
Given:
The picture of the map is attached. ( Missing from the question ).
Find:
The effect of force as it travels along each direction.
Solution:
- We know the relationship between change in potential and the force acting on the charge particle is given by:
F = - q*dV/ dr
Where,
q : Charge of the particle
V : Volt potential
dV/dr : Potential difference along a direction.
Direction 1:
- The color code of the map changes as the particle moves along this direction. Each color code represents a potential difference. So as the particle moves between different potential difference then according to the relationship given above The force varies along varies as particle moves from one color to another. Hence, a non zero force but not constant.
Direction 2:
- In the direction 2, the charged particle moves along the same color. The potential difference for each color is constant. Hence, according to the relationship of potential difference and force. If potential difference is constant then the Electrostatic Force on the charge is also constant. Hence, Force is non-zero and constant.
I don’t understand the question
Answer:
a) 
b) 
Explanation:
Given:
mass of ball, 
initial speed of the ball, 
mass of the person, 
a)
Using the conservation of linear momentum:
When the person catches the ball, assuming that the person catches it with an impact without absorbing the shock.



b)
When the ball hits the person and bounces off with the velocity of
.
Using the conservation of linear momentum:

where:
final speed of the ball after collision
final speed of the person after collision
initial velocity of the person = 0
putting the respective values in the above eq.


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.