Answer:51.44 units
Explanation:
Given
x component of vector is 
y component of vector is 
so position vector is

Magnitude of vector is


|r|=51.44 units
Direction

vector is in 2nd quadrant thus


Answer:
The maximum speed at which the car can safety travel around the track is 18.6m/s.
Explanation:
Since the car is in circular motion, there has to be a centripetal force
. In this case, the only force that applies for that is the static frictional force
between the tires and the track. Then, we can write that:

And since
and
, we have:

Now, if we write the vertical equation of motion of the car (in which there are only the weight and the normal force), we obtain:

Substituting this expression for
and solving for
, we get:

Finally, plugging in the given values for the coefficient of friction and the radius of the track, we have:

It means that in its maximum value, the speed of the car is equal to 18.6m/s.
It's the node of the standing wave.
Answer:


Explanation:
h = Planck's constant = 
c = Speed of light = 
m = Mass of electron = 
= Work function = 
= Velocity of A particle = 
= Velocity of B particle = 
The wavelength is given by


The wavelength 

The wavelength 