Answer:
50m; 0m/s.
Explanation:
Given the following data;
Initial velocity = 20m/s
Acceleration, a = - 4m/s²
Time, t = 5secs
To find the displacement, we would use the second equation of motion;

Substituting into the equation, we have;



S = 50m
Next, to find the final velocity, we would use the third equation of motion;
Where;
- V represents the final velocity measured in meter per seconds.
- U represents the initial velocity measured in meter per seconds.
- a represents acceleration measured in meters per seconds square.
<em>Substituting into the equation, we have;</em>
V = 0m/s
<em>Therefore, the displacement of the bus is 50m and its final velocity is 0m/s.</em>
Answer:
The sum of PE and KE remains constant
Explanation:
The electrostatic force between two charges is inversely
proportional to the square of the distance between them.
So if you want to multiply the force by, say, ' Q ',
you need to multiply the distance by ( 1 / √Q ) .
We want to multiply the force by 16, so we need to
multiply the distance by ( 1 / √16 ) = ( 1 / 4 ) .
The distance should be changed to 1/4 of what it is now.
Let's see: frequency of cellular phone waves (GSM phones) is (800-1900 MHz). If we look at the table of the electromagnetic spectrum, we can see that this range is contained within the frequencies of the microwaves, which include waves in the range 300 MHz-300 GHz.
So, summarizing, the correct answer is "microwaves".