Answer: A)
Explanation: when an electron is placed in a magnetic field, it experiences a force.
This force is given below as
F=qvB*sinθ
F = force experienced by charge.
q = magnitude of electronic charge
v = speed of electron
B= strength of magnetic field
θ = angle between magnetic field and velocity.
What defines the force exerted on the charge is the angle between the field and it velocity.
If magnetic field is parallel to velocity, then it means that θ=0° which means sin 0 = 0, which means
F = qvB * 0 = 0.
The charge being at rest has nothing to do with the angle between magnetic field strength and velocity.
Answer:
f = 8 N
Explanation:
Data provided in the question
Radius of the pulley = r = 0.05 m
Moment of inertia = (I) = 0.2 kg.m^{2}
Angular acceleration = ∝ = 2 rad/sec
Based on the above information
As we know that
Torque is
And,
Torque is also
So,
We can say that
0.05f = 0.4
f = 8 N
We simply applied the above formulas
Answer:
F = 2,894 N
Explanation:
For this exercise let's use Newton's second law
F = m a
The acceleration is centripetal
a = v² / r
Angular and linear variables are related.
v = w r
Let's replace
F = m w² r
The radius r and the length of the rope is related
cos is = r / L
r = L cos tea
Let's replace
F = m w² L cos θ
Let's reduce the magnitudes to the SI system
m = 101.7 g (1 kg / 1000g) = 0.1017 kg
θ = 5 rev (2π rad / rev) = 31,416 rad
w = θ / t
w = 31.416 / 5.1
w = 6.16 rad / s
F = 0.1017 6.16² 0.75 cos θ
F = 2,894 cos θ
The maximum value of F is for θ equal to zero
F = 2,894 N
