Answer:
W = 0.842 J
Explanation:
To solve this exercise we can use the relationship between work and kinetic energy
W = ΔK
In this case the kinetic energy at point A is zero since the system is stopped
W = K_f (1)
now let's use conservation of energy
starting point. Highest point A
Em₀ = U = m g h
Final point. Lowest point B
Em_f = K = ½ m v²
energy is conserved
Em₀ = Em_f
mg h = K
to find the height let's use trigonometry
at point A
cos 35 = x / L
x = L cos 35
so at the height is
h = L - L cos 35
h = L (1-cos 35)
we substitute
K = m g L (1 -cos 35)
we substitute in equation 1
W = m g L (1 -cos 35)
let's calculate
W = 0.500 9.8 0.950 (1 - cos 35)
W = 0.842 J
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
Average speed is defined as the ratio of total distance covered in total given time

here we know that total distance that man moved is


so total distance is



now here total time of the motion is


total time will be given as


now by above formula


so his average speed is 30 km/h
The response is False, both bars, iron bars and plastic
bars have de same inertia, this characteristic does not depend on the type of
material, the inertia depends on his transverse section, since we can estimate
in the following formula
<span>Area moment of inertia Ixx = BH3/12</span>
<span>Area moment of inertia Iyy= HB3/12</span>
D. all of these
all of these use electricity
Hope I helped!