Answer:

Explanation:
As we know that when electron moved in electric field then work done by electric field must be equal to the change in kinetic energy of the electron
So here we have to find the work done by electric field on moving electron
So we have



now the distance moved by the electron is given as

so we have



now we have to convert it into keV units
so we have


Answer:
to prevent cuz now for my mind when you prevent it it will not happen to you or nothing happened to you
When the object is at the top of the hill it has the most potential energy. If it is sitting still, it has no kinetic energy. As the object begins to roll down the hill, it loses potential energy, but gains kinetic energy. The potential energy of the position of the object at the top of the hill is getting converted into kinetic energy. Hope this helped. :)
Answer:
1. 218.55 N
2. 
3. 
Explanation:
Part 1;
Net force
where m is mass, g is gravitational force and
is the angle of inclination

Frictional force,
is given by
where
is the coefficient of static friction


Since
, therefore, the block doesn’t slip and the frictional force acting is mgh=218.55N
Part 2.
Using the relationship that
Frictional force 



The maximum angle of inclination 

Part 3:
Net force on the object is given by
where
is the coefficient of kinetic friction

= 9.8 ( sin 38 - (0.51) cos 38 )
= 
Answer:
Explanation:
A charge is produced when an atom losses or gains an electron. The law of static electricity states that like charges repels, while unlike charges attracts.
1. To determine the charge on the polystyrene rod.
Place the polystyrene rod on the non-conducting rotating stand, and bring the positively charged rod close to it. If attraction occurs, it shows that it is oppositely charged. If repulsion occurs, it shows that it is positively charged.
Bringing a negatively charged rod close to the rotating polystyrene rod would attract it if the charge is opposite. But if the charge on the two rods are the same, repulsion occurs.
2a. When the polystyrene rod is positively charged, it would attract the negatively charged rod but repel the positively charged rod.
b. When the polystyrene rod is negatively charged, it would repel the negatively charged rod but attract the positively charged rod.
c. When the polystyrene rod is uncharged, no reaction would be observed when either the positively charged or negatively charged rod is brought close to it.