Answer:
The angular acceleration of the wheel is -6.54 rad/s²
Explanation:
We'll use the equations of motion for this.
w = 2πf
f = 75 rpm = 1.25 rps = 1.25 rev/s
w₀ = initial angular velocity = 2π × 1.25 = 7.85 rad/s
w = final angular velocity = 0 rad/s
t = 1.2 s
α = ?
w = w₀ + αt
0 = 7.85 + 1.2α
α = 7.85/1.2 = - 6.54 rad/s²
Explanation:
Draw a free body diagram for each disc.
Disc A has three forces acting on it: 86.5 N up, T₁ down, and Wa down.
∑F = ma
86.5 N − T₁ − Wa = 0
Wa = 86.5 N − T₁
ma × 9.8 m/s² = 86.5 N − 55.6 N
ma = 3.2 kg
Disc B has three forces acting on it: T₁ up, T₂ down, and Wb down.
∑F = ma
T₁ − T₂ − Wb = 0
Wb = T₁ − T₂
mb × 9.8 m/s² = 55.6 N − 36.5 N
mb = 1.9 kg
Disc C has three forces acting on it: T₂ up, T₃ down, and Wc down.
∑F = ma
T₂ − T₃ − Wc = 0
Wc = T₂ − T₃
mc × 9.8 m/s² = 36.5 N − 9.6 N
mc = 2.7 kg
Disc D has two forces acting on it: T₃ up and Wd down.
∑F = ma
T₃ − Wd = 0
Wd = T₃
md × 9.8 m/s² = 9.6 N
md = 0.98 kg
Answer:
It cannot be constant because if it does not change and each time it increases its strength and speed.
Explanation:
To be effective, an exercise program must have an aerobic
form, portion for strength enhancement, and a stretching part. These three
things are essential because they each target specific improvements in your
body. For example, aerobics can help you maintain your body’s fitness or make
it better. This usually targets your heart rate and ensures that you burn fat
while doing so. Second is strength enhancement; this will make sure that your
body becomes better – not just in a feeble state. Lastly is stretching, your
muscles are like rubber bands. You cannot end or start your exercise program
without stretching simply because they can damage your muscles as well. Aside
from this, stretching can stop you from shocking your body into a physical
activity, which may cause you to lose consciousness or have undue stress and fatigue.
