Answer:
the rate of acceleration of the train is 4 m/s²
Explanation:
Given;
initial velocity of the train, u = 10 m/s
change in time of motion, dt = 5 s
final velocity of the train, v = 30 m/s
The rate of acceleration of the train is calculated as;
Therefore, the rate of acceleration of the train is 4 m/s²
Answer:
t = 4.21x10⁻⁷ s
Explanation:
The time (t) can be found using the angular velocity (ω):
<em>Where θ: is the angular displacement = π (since it moves halfway through a complete circle)</em>
We have:
<u>Where</u>:
<em>v: is the tangential speed </em>
<em>r: is the radius</em>
The radius can be found equaling the magnetic force with the centripetal force:
Where:
m: is the mass of the alpha particle = 6.64x10⁻²⁷ kg
q: is the charge of the alpha particle = 2*p (proton) = 2*1.6x10⁻¹⁹C
B: is the magnetic field = 0.155 T
Hence, the time is:
Therefore, the time that takes for an alpha particle to move halfway through a complete circle is 4.21x10⁻⁷ s.
I hope it helps you!
Answer:
The force exerted by the biceps is 143.8 kgf.
Explanation:
To calculate the force exerted by the biceps, we calculate the momentum in the elbow.
This momentum has to be zero so that her forearm remains motionless.
Being:
W: mass weight (6.15 kg)
d_W= distance to the mass weight (0.425 m)
A: weight of the forearm (2.25 kg)
d_A: distance to the center of mass of the forearm (0.425/2=0.2125 m)
H: force exerted by the biceps
d_H: distance to the point of connection of the biceps (0.0215 m)
The momemtum is:
The force exerted by the biceps is 143.8 kgf.
