Answer:
Explanation:
Given that
The mass of the body is 0.04kg
M=0.04kg
The radius of the paths is 0.6m
r=0.6m
The normal force exerted at A is 3.9N
Fa=3.9N
The normal force exerted at B is 0.69N
Fb=0.69N
Then work done by friction from point A to B will be the change in K.E
W=∆K.E+P.E
So we need to know the velocity at both point A and B
Then since the centripetal force is given as
Ft=mv²/r
Then,
For point A
Fa=mv²/r
3.9=0.04v²/0.6
3.9=0.0667v²
v²=3.9/0.0667
v²=58.5
v=√58.5
v=7.65m/s
Va=7.65m/s
Now at point B
Fb=mv²/r
0.69=0.04v²/0.6
0.69=0.0667v²
v²=0.69/0.0667
v²=10.35
v=√10.35
v=3.22m/s
Vb=3.22m/s
Then, the work done is
W=∆K.E+P.E
P.E is given as mgh
The height will be 2R =1.2m
P.E=mgh
P.E=0.04×9.81×1.2
P.E=0.471J
Final kinetic energy at B minus initial kinetic energy at A
W=K.Eb-K.Ea
K.E is given as 1/2mv²
W=1/2m(Vb²-Va²) +P.E
W=0.5×0.04(3.22²-7.65²) +0.471
W=0.5×0.04×(-48.1541) +0.471
W=-0.96+0.471
W=-0.49J
work was done on the block by friction during the motion of the block from point A to point B is 0.49J.
Friction opposes motions and that is why the work done is negative
They traveled for six hours and forty two minutes
I believe the correct answer is B.<span>positively charged hair.</span>
Acceleration due to gravity depends directly on the mass of Earth and inversely to the square of radius of Earth.
Answer:
1) x_total = 2.7 km=2700 m, 2) t_total = 1926 s, 3) v_avg = 1.40 m / s
Explanation:
1) To solve this uniform velocity problem, we must find the displacement of each part and add them.
x_total = x₁ + x₂
x_total = 0.7 + 2.0
x_total = 2.7 km
2) how long does it take for this tour
truck
v = x₁ / t₁
t₁ = x₁ / v
t₁ = 0.7 / 20
t₁ = 0.035 h
Let's reduce the time to the SI system
t₁ = 0.035 h (3600 s / 1h) = 126 s
when he is walking
t₂ = 30 min (60 s / 1min) = 1800 s
the total time is
t_total = t₁ + t₂
t_total = 126 + 1800
t_total = 1926 s
3) the average velocity is defined as the displacement in the inerval between time
v_avg = x_total / t_total
v_avg = 2700/1926
v_avg = 1.40 m / s