Answer:
40J
Explanation:
Kinetic energy = 1/2 mv^2
Where m = mass and
v = velocity
Given mass = 20kg
v = 2m/s
K.E = 1/2 x 20 x2^2
= 1/2 x 20 x 2 x 2
= 80/2
= 40J
C
The atomic mass is the sum of the number of neutrons and protons.
B = 0.018 T Ans,
Since, it is moving in a circular path, thus, centripetal force will act on it i.e.
F =

where, m is the mass of the object, v is the velocity and r is the radius of circular path.
And, since a positive charge is moving, it will create magnetic force which is equal to F = qvB
where q is the charge, v is the velocity of the particle and B is the magnetic field.
Now, the two forces will be equal,
i.e.

= qvB
⇒

= qB
⇒B =

<span>putting the values, we get,
</span>
use q = 1.6 * 10^ -19
⇒ B = 0.018 T
A waves frequency (in Hertz) is how many crests pass by a point per second. easily confused with period, which is the amount of time it takes for a full wave to pass by a certain point