The speed of a moving bullet can be determined by allowing the bullet to pass through two rotating paper disks mounted a distance
87 cm apart on the same axle. from the
angular displacement of 21.6◦
of the two bullet holes in the disks and the rotational speed
537 rev/min of the disks, we can determine
the speed of the bullet.
what is the speed of the bullet?
answer in units of m/s.

130 m/s

Explanation:

First use the angular displacement to find the time.

Δθ = ω t

21.6° × (1 rev / 360°) = 537 rev/min × (1 min / 60 s) t

t = 0.0067 s

Now use the distance to find the speed.

v = Δx / t

v = 0.87 m / 0.0067 s

v = 130 m/s

okay i have so many questions. but the big one here is: um wt..f is this mess? ?

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day