Answer:
Quick question do you mean what are some safety rules
Explanation:
Crosswalk, Stop sign,
Answer: part a: 19.62m
part b: 19.62 m/s
part a: 2.83 secs
Explanation:If the air resistance is ignored then the swimmer experience free fall under gravity hence
u=0
a=9.81 m/s2
t=2 secs

s=h

Part b

Part c
now we have h=2*19.62=39.24

Answer:

The Magnitude of electric field is in the upward direction as shown directly towards the charge
.
Explanation:
Given:
- side of a square,

- charge on one corner of the square,

- charge on the remaining 3 corners of the square,

<u>Distance of the center from each corners</u>


∴Distance of center from corners, 
Now, electric field due to charges is given as:

<u>For charge
we have the field lines emerging out of the charge since it is positively charged:</u>

<u>Force by each of the charges at the remaining corners:</u>

<u> Now, net electric field in the vertical direction:</u>


<u>Now, net electric field in the horizontal direction:</u>


So the Magnitude of electric field is in the upward direction as shown directly towards the charge
.
Answer:
Changes in the object's momentum (answer D)
Explanation:
A net force will cause an object to change its velocity, and that will affect the object's momentum, which is defined by the product of the object's mass times its velocity.
So, select the last option (D) in the given list.
Answer:
c Like/same signs
Explanation:
A repelling force occurs between two or more charged objects with the charges are of like or same sign.
- According to Coulombs law, like charges repel on another, unlike charges attracts on another.
- If a positive charge comes into the vicinity of another positive charge, there will be repulsion.
- When oppositely charge species are brought near each other, there is an attraction.
Therefore, repulsion occurs when like charges are brought close to each other.