Hey there!
We are given ,
Acceleration, a = -2m/s^2
Initial velocity , u = 15m/s
Time , t = 5 seconds
We know that ,
V=u+at
Now , final speed ,
V = 15+(-2)(5)
V = 15-10
V = 5 m/s -> final speed
Hope this helps you dear :)
Have a good day <3
Answer:
Should place the current perpendicular to the magnetic field
Explanation:
The magnetic force exerted on a current-carrying wire is given by
where
I is the current in the wire
L is the length of the wire
B is the magnetic field
is the angle between the direction of the wire and the magnetic field
As we see from the formula, the magnetic force is maximum when
which means
So, when the current in the wire and the magnetic field are perpendicular to each other.
Answer:
A
Explanation:
Let's rule out some of the options. C makes no sense because static charges will create electric fields only, so the charge has to move. D makes no sense because monopoles do not exist. We can rule out B because when a charge is moving at a constant velocity. You can use Maxwell's equations and general relativity to figure out that at a constant velocity, you can't produce an electromagnetic wave because there is no magnetic field. Therefore the answer is A. When you have an oscillating or accelerating electric charge, you will produce an EM wave.
<span> B) Sound waves transmit energy through all forms of matter. </span>
Answer:
K remains constant
Explanation:
The magnetic force does not do any work on the ion.
In fact, the magnetic force due to a magnetic field is always perpendicular to the motion of the charge itself. Keep in mind that the work done by a force is given by
where F is the magnitude of the force, d is the displacement of the particle, and is the angle between the direction of the force and the displacement. Since the magnetic force is perpendicular to the displacement of the ion, then and , so the work done is zero.
For the work-energy theorem, the work done on the ion is equal to the variation of its kinetic energy:
However, since W=0, then , which means that the kinetic energy of the ion does not change.