Answer:
The wave speed is calculated below:
Explanation:
Given,
number of waves passed per minute = 8
time period = 1 minute = 60 s
distance between successive wave crests = 20 m
waves passing interval per second =

Now,
wave speed = 20 m ×

=
m/s
= 2.67 m/s
Hence the wave speed is 2.67 m/s.
The magnetic force (Lorentz force) experienced by the proton in the magnetic field is given by

since

, because the velocity v and the force F in this problem are perpendicular, and so also the angle

between the velocity and the magnetic field B should be

.
Let's find the magnitude of the magnetic field; this is given by

To understand the direction, let's use the right-hand rule:
-index finger: velocity
- middle finger: magnetic field
- thumb: force
Since the velocity (index) points east and the force (thumb) points south, then the magnetic field (middle finger) points downwards. So we write:
B = -0.091 T
Answer:
3) None of the above
Explanation:
In orbital motion
by lepler law:
Planet sweeps out equal area in equal of time, so angular velocity is conserved.
Angular momentum is also conserved,
so option, 3) None of the above is right.
Hi there!
Begin by using Gauss' Law to find the electric field.

E = Electric field (N/C)
dA = differential area element
Q = enclosed charge (C)
ε₀ = Permittivity of free space (8.85 * 10⁻¹² C²/Nm²)
We can construct a large cylinder around the wire in order to determine the electric flux. The electric field lines will pass through the LATERAL surface area of the cylinder, so:

Where 'L' is the length of the cylinder and 'r' is the distance from the capacitor.
The enclosed charge is equivalent to the charge per meter length (λ) multiplied by the length, so:

We can rewrite the dot product as EA (where cosθ = 1 since the normal vector points in the direction of the field).
A = the lateral surface area of a cylinder, so:

Rearrange to solve for 'E'.

a)
Plug in the distance into 'r'.

b)
Repeat:

We can see that the distance from the wire is INVERSELY related to the electric field strength by a power of r⁻¹. The field strength DECREASES as the distance INCREASES.