Complete Question
The complete question is shown on the first uploaded image
Answer:
The velocity is 
in positive x -direction
The speed is 
Explanation:
From the question we are told that
The distance from the house to truck is D = 20 m
The distance traveled back to retrieve wind-blown hat is d = 15
The distance from the wind-blown hat position too the truck is k = 20 m
The total time taken is t = 75 s
Generally when calculating the displacement the Justin's backward movement to collect his wind - blown hat is taken as negative
Generally Justin's displacement is mathematically represented as
=> 
Generally the average velocity is mathematically represented as
=> 
=>
Generally the distance covered by Justin is mathematically represented as
=> 
=> 
Generally Justin's average speed over a 75 s period is mathematically represented as
=> 
=>
The answer is 100 my nilla.
Answer:
The correct answer is A
Explanation:
The question requires as well the attached image, so please see that below.
Coulomb's Law.
The electrical force can be understood by remembering Coulomb's Law, that describes the electrostatic force between two charged particles. If the particles have charges 
and 
, are separated by a distance r and are at rest relative to each other, then its electrostatic force magnitude on particle 1 due particle 2 is given by:
Thus if we decrease the distance by half we have
So we get
Replacing we get
We can then multiply both numerator and denominator by 4 to get
So we have
Thus if we decrease the distance by half we get four times the force.
Then we can replace the second condition
So we get
which give us
Thus doubling one of the charges doubles the force.
So the answer is A.
Acceleration = (change in speed) / (time for the change)
-- You said that the airplane has to speed up from zero ("sitting") to 40 m/s, so the change in speed is 40 m/s.
-- You said that it has to roll for 10 seconds to build up enough speed to take off, so the time for the change is 10 s .
Acceleration = (40 m/s) / (10 s)
Acceleration = (40/10) (m/s)/s
<em>Acceleration = 4 m/s²</em>
That seems like no problem. It's only like about 41% of 1 G . That would not even spill the drinks in First Class, or wake up the passengers who are already asleep (like me).
