Answer:51.44 units
Explanation:
Given
x component of vector is 
y component of vector is 
so position vector is

Magnitude of vector is


|r|=51.44 units
Direction

vector is in 2nd quadrant thus


Answer:
Los objetos A y C tienen cargas del mismo signo (opcion a)
Explanation:
Hay dos tipos de cargas
: cargas positivas y cargas negativas.
La Ley de Coulomb dice que la fuerza electrostática entre dos cargas puntuales es proporcional al producto de las cargas e inversamente proporcional al cuadrado de la distancia que las separa, y tiene la dirección de la línea que las une y se cumple que:
- La fuerza ejercida sobre una carga apunta hacia la otra cuando las dos tienen distinto signo (fuerza atractiva).
- El sentido de la fuerza se dirige hacia el lado opuesto de la carga cuando ambas tienen el mismo signo (fuerza repulsiva).
Es decir que las cargas de igual signo se repelen, mientras que las de diferente signo se atraen.
Entonces, si se juntan los objetos A y B y se repelen significa que la carga es del mismo signo.
Cuando se acercan los objetos B y C, se repelen. Entonces significa que posee carga de igual signo.
Por lo que podes concluir que <u><em>los objetos A y C tienen cargas del mismo signo (opcion a)</em></u>
Hello there!
I hope you and your family are staying safe and healthy during this unprecendented time.
A) What is the work done?
Answer: We need to use the formula



B) What is the work done on the cart by the gravitational force?
Alright, we know that the gravitional force is perpendicular to the diplacement. Therefore, we gonna use the following formula:


C) What is the work done on the cart by the shopper?
This is the easier part, since we already know that the work done by the shopper is the same as the work done by the friction force

D) Find the force the shopper exerts, using energy considerations.

E) What is the total work done?
You just need to add them:

Clear question is;
An ice cube is placed in the sun. Later there is a puddle of water. Later still the puddle is gone. What kind of change has occurred?
Answer:
Physical change.
Explanation:
There are two type of changes called physical change and chemical change.
In Physical changes, there is only change in the appearance of the substance and not its chemical composition. Whereas, in Chemical changes the substance changes entirely into another substance with a new chemical formula.
Now, for the ice cube, it has melted from a solid state to a liquid state. Thus, there is only a change in appearance and not its chemical composition. Thus, it's a physical change that has occurred.