A material that has high resistance to the flow of electric current is called an electric resistor
Answer:

Explanation:
The electrostatic potential energy is given by the following formula

Now, we will apply this formula to both cases:

So, the change in the potential energy is

Answer:
12.5 m/s
Explanation:
From the question given above, the following data were obtained:
Initial velocity (u) = 0 m/s
Height (h) = 8 m
Final velocity (v) at 8 m above the lowest point =?
NOTE: Acceleration due to gravity (g) = 9.8 m/s²
The velocity of the roller coaster at 8 m above the lowest point can be obtained as follow:
v² = u² + 2gh
v² = 0² + (2 × 9.8 × 8)
v² = 0 + 156.8
v² = 156.8
Take the square root of both side
v = √156.8
v = 12.5 m/s
Therefore, the velocity of the roller coaster at 8 m above the lowest point is 12.5 m/s.
Answer:
Your friend is 2.143 blocks from the restaurant.
You are 2.857 blocks from the restaurant.
Explanation:
Let t be the time both you and your friend take to walk to the restaurant.
The distance (m) from your building to the restaurant is your walking time t times your speed v1

Similarly the distance (m) from your friend building to the restaurant:

Let b be the length (in m) of a block, the total distance of 5 blocks is 5b





So your friend are 2.143b meters from the restaurant, since each block is b meters long, 2.143b meters would equals to 2.143b/b = 2.143 blocks. And you are 5 - 2.143 = 2.857 blocks from the restaurant.
Answer: D
All the particles must be uncharged
Explanation:
If all the particles are positively charged, then there will be force of repulsion between them which will give different directions away from each other. The same is applicable if they are all negatively charged.
If the particles are positively and negatively charged, their will be force of attraction between them which will give different directions towards each other.
For all to be experiencing forces in the same direction, We can conclude that
All the particles must be uncharged.