<span>In order for the results to be valid, the dependent variable can only be affected by the independent variable, so somethings need to be kept constant. The things that need to be kept constant are called controlled variables.</span>
Answer:
The ratio of electric force to the gravitational force is 
Explanation:
It is given that,
Distance between electron and proton, 
Electric force is given by :

Gravitational force is given by :

Where
is mass of electron, 
is mass of proton, 
is charge on electron, 
is charge on proton, 



So, the ratio of electric force to the gravitational force is
. Hence, this is the required solution.
Answer: negative acceleration
Explanation:
Acceleration is speeding up, the ball is slowing down making it negative acceleration
Answer:
d=9.462×10^15 meters
Explanation:
<u>Relation between distance, temps and velocity:</u>
d=v*t
t=1year*(365days/1year)*/(24hours/1day)*(3600s/1h)=31536000s
So:
1 light year=d=3*10^8m/s*3.154*10^7s=9.462×10^15 meters
Answer: A material that does not easily allow a charge to pass through it is called an Plastic and rubber are good insulators. Many types of electric wire are covered with plastic, which insulates well. The plastic allows a charge to be conducted from one end of the wire to the other, but not through the sides of the wire.
Explanation: