Answer:

Explanation:
Given:
- charge on the alpha particle,

- mass of the alpha particle,

- strength of a uniform magnetic field,

- radius of the final orbit,

<u>During the motion of a charge the magnetic force and the centripetal forces are balanced:</u>


where:
v = velocity of the alpha particle



Here we observe that the velocity of the aprticle is close to the velocity of light. So the kinetic energy will be relativistic.
<u>We firstly find the relativistic mass as:</u>



now kinetic energy:



Answer: 7.5 rev/s
Explanation:
We are given the angular velocity
a helicopter's main rotor blades:

However, we are asked to express this
in the International Systrm (SI) units. In this sense, the SI unit for time is second (
):


Answer: 7.41 m/s
Explanation: By using the law of of energy, kinetic energy of the brick as it falls equals the potential energy before falling.
Kinetic energy = mv²/2, potential energy = mgh
mv²/2 = mgh
v²/2 = gh
v² = 2gh
v = √2gh
Where g = 9.8 m/s², h = 2.80m
v = √2×9.8×2.8 = 7.41 m/s
No, because in oxygen depraved rooms, if you drop a feather and a bowling ball at the same height and time, they will fall at the same speed and have the same amount of impact.