Answer:
20.96 h
Explanation:
The perimeter of the track is 2*pi*r = 20pi miles
In 10 hours, car B would have moved 20miles. So, when Car A leaves from point X, car B is 20pi - 20 miles from point X counter-clockwise and car A.
From here, we can express the distance of A from X like this:
xa = 3t
And the distance of B would be:
xb = 20pi - 20 - 2t
The time t where they would passed each other and put 12 miles between them would be the one where xa - xb is equal to 12:
xa - xb = 12
3t - (20pi - 20 - 2t) = 12
5t = 20 pi - 8
t = (20pi - 8)/5 = 10.96 h
Remember to add this value to the 10 hours car B had already been racing:
t = 20.96h
Answer:
The magnitude of the electric field be 171.76 N/C so that the electron misses the plate.
Explanation:
As data is incomplete here, so by seeing the complete question from the search the data is
vx_0=1.1 x 10^6
ax=0 As acceleration is zero in the horizontal axis so
Equation of motion in horizontal direction is given as
Now for the vertical distance
vy_o=0
than the equation of motion becomes
Now using this acceleration the value of electric field is calculated as
Here a is calculated above, m is the mass of electron while q is the charge of electron, substituting values in the equation
So the magnitude of the electric field be 171.76 N/C so that the electron misses the plate.
Answer:
The energy that the truck lose to air resistance per hour is 87.47MJ
Explanation:
To solve this exercise it is necessary to compile the concepts of kinetic energy because of the drag force given in aerodynamic bodies. According to the theory we know that the drag force is defined by
Our values are:
Replacing,
We need calculate now the energy lost through a time T, then,
But we know that d is equal to
Where
v is the velocity and t the time. However the time is given in seconds but for this problem we need the time in hours, so,
(per hour)
Therefore the energy that the truck lose to air resistance per hour is 87.47MJ
Answer: The correct answers are (A) and (C).
Explanation:
The expression from electrostatic force is as follows;
Here, F is the electrostatic force, k is constant, r is the distance between the charges and are the charges.
The electrostatic force follows inverse square law. It is inversely proportional to the square of the distance between the charges. It is directly proportional to the product of the charges.
Like charges repel each other. There is a force of electrostatic repulsion between the like charges. Unlike charges attract each other. There is a force of electrostatic attraction between unlike charges.
The charges are induced on the neutral object when it is placed nearby the charged object without actually touching it.
Therefore, the true statements from the given options are as follows;
Like charges repel.
Unlike charges attract.