Answer:
5694000 min
Explanation:
Let's suppose the average American watches 4 hours of TV every day. First, we will calculate how many minutes they watch per day. We will use the conversion factor 1 h = 60 min.
(4 h/day) × (60 min/1 h) = 240 min/day
They watch 240 minutes of TV per day. Now, let's calculate how many minutes they watch per year. We will use the conversion factor 1 year = 365 day.
240 min/day × (365 day/year) = 87600 min/year
They watch 87600 min/year. Finally, let's calculate how many minutes they spend watching TV in 65 years.
87600 min/year × 65 year = 5694000 min
Answer:
a) α = 0.338 rad / s² b) θ = 21.9 rev
Explanation:
a) To solve this exercise we will use Newton's second law for rotational movement, that is, torque
τ = I α
fr r = I α
Now we write the translational Newton equation in the radial direction
N- F = 0
N = F
The friction force equation is
fr = μ N
fr = μ F
The moment of inertia of a saying is
I = ½ m r²
Let's replace in the torque equation
(μ F) r = (½ m r²) α
α = 2 μ F / (m r)
α = 2 0.2 24 / (86 0.33)
α = 0.338 rad / s²
b) let's use the relationship of rotational kinematics
w² = w₀² - 2 α θ
0 = w₀² - 2 α θ
θ = w₀² / 2 α
Let's reduce the angular velocity
w₀ = 92 rpm (2π rad / 1 rev) (1 min / 60s) = 9.634 rad / s
θ = 9.634 2 / (2 0.338)
θ = 137.3 rad
Let's reduce radians to revolutions
θ = 137.3 rad (1 rev / 2π rad)
θ = 21.9 rev
Electron volts...........
Answer:
The diameter of the needle is <u>4.675 cm</u>.
Explanation:
Given:
Volume flow rate is, 
Velocity of air expelled by pump is, 
Let the area of the needle be 'A' cm² and the diameter be 'd' cm.
We know that, volume flow rate of the air expelled by pump is given as the product of the needle's area and velocity of air flowing through that area.
Therefore, volume flow rate is given as:
Now, considering the needle to be circular, area of the needle can be written as:
Therefore, the diameter of the needle is 4.675 cm.
Answer:
238 cm3
Explanation:
You take the formula for volume, V = 2500.0 g/10.5 g/cm3 = 238.095 = 238 cm3. The answer is rounded to 3 significant figures.
