Answer:1.008 ×10^-14/rJ
Where r is the distance from.which the charge was moved through.
Explanation:
From coloumbs law
Work done =KQq/r
Where K=9×10^9
Q=7×10^-6C
q=e=1.6×10^-19C
Micro is 10^-6
W=9×10^9×7×10^-6×1.6×10^-19/r=100.8×10^-16/r=1.008×10^-14/rJ
r represent the distance through which the force was used to moved the charge through.
Answer:
106.7 N
Explanation:
We can solve the problem by using the impulse theorem, which states that the product between the average force applied and the duration of the collision is equal to the change in momentum of the object:

where
F is the average force
is the duration of the collision
m is the mass of the ball
v is the final velocity
u is the initial velocity
In this problem:
m = 0.200 kg
u = 20.0 m/s
v = -12.0 m/s

Solving for F,

And since we are interested in the magnitude only,
F = 106.7 N
A=F/m
a=(3000000)/(20000)
a=15 m/s^2
<u>Answer:</u>
<em>The initial distance between the trains is 1450 m.
</em>
<u>Explanation:</u>
In the question two trains are of equal length 400 m and moves at a uniform speed of 72 km/h. train A is moving ahead of train B. If the train B has to overtake train A it should accelerate.
Train B’s acceleration is
and it accelerated for 50 seconds.
<em>
</em>
<em>t=50 s
</em>
<em>initial speed u=72km/h
</em>
<em>we have to convert this speed into m/s </em>
<em>
</em>
<em>Distance covered in accelerating phase
</em>
<em>
</em>
<em>
</em>
If a train is just behind another, the distance covered by the train located behind during overtaking phase will be equal to the sum of the lengths of the trains.
<em>Here length of train A+length of train
</em>
<em>Hence the initial distance between the trains =
</em>