Answer:
Magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion. It is the basic force responsible for such effects as the action of electric motors and the attraction of magnets for iron. Electric forces exist among stationary electric charges; both electric and magnetic forces exist among moving electric charges. The magnetic force between two moving charges may be described as the effect exerted upon either charge by a magnetic field created by the other.
Answer:
Time = 11.60 seconds.
Explanation:
Speed can be defined as distance covered per unit time. Speed is a scalar quantity and as such it has magnitude but no direction.
Mathematically, speed is given by the equation;

Given the following data;
Speed = 0.711m/s
Distance = 8.25m
To find the time;
Making time the subject of formula, we have;
Substituting into the equation, we have;

Time = 11.60 secs.
Answer:
(a) Length =136.58 m
(b) T=5995 N
Explanation:
for the glider in the back
T - 1900 = 700 a
for the glider in front
12000-T -1900 = 700a
add equations
12000-3800 = 1400 a
a=5.85 m/s^2
v^2 = v0^2 + 2 a x
40^2 = 2*5.85*x
Length =136.58 m
b) plug the a back into one of the previous formula
T - 1900 = 700*5.85
T=5995 N
Dipper effect of an oncoming train get louder as it approaches and sound diminishes as it goes away sound traveling