Answer:
v = 36.05 m/s
Explanation:
It is given that,
Initial speed of the parachutist, u = 14.8 m/s
Altitude, h = 55.1 m
The acceleration due to gravity,
Let v is the speed of the shoe just before it hits the ground. The third equation of motion is given by :
v = 36.05 m/s
So, the speed of the show just before it hits the ground is 36.05 m/s. Hence, this is the required solution.
Answer= D. Velocity includes a direction; speed does not.
Velocity and speed both have the same units of m/s, so answers A and B are wrong.
Velocity is a vector quantity and so has direction and magnitude, so C is wrong.
Speed is a scalar quantity, only having magnitude and no direction.
<span>The magnitude of her acceleration as she travels this 12 meters is 1.875m/s^2</span>
Answer:
angular speed = 0.4 rad/s
Explanation:
given data
radius = 5 m
moment of inertia = 2000 kg-m²
angular speed = 1.0 rad/s
mass = 60 kg
to find out
angular speed
solution
Rotational momentum of merry-go-round = I?
we get here momentum that is express as
momentum = 2000 × 1
momentum = 2000 kg-m²/s
and
Inertia of people will be here as
Inertia of people = mr² = 60 × 5²
Inertia of people = 1500 kg-m²
so Inertia of people for two people
1500 × 2 = 3000
and
now conserving angular momentum(ω)
moment of inertia × angular speed = ( momentum + Inertia of people ) angular momentum
2000 × 1 = (2000 + 3000 ) ω
solve we get now
ω = 0.4 rad/s
Answer
79.8 miles per hours fast is the car going.
Formula
By using the dopplers effect. (When source is approching .)
As given
A car approaches you with its horn blowing.
The observed frequency is 503.7 Hz.
The speed of sound is 1100 ft/s .
The car's horn has a frequency of 450 Hz.
i.e
v = 1100 ft/s
Put in the above formula
Now convert 117.3 ft per second into miles per hours.
117.3 feet per second = 79.8 miles per hours (Approx)
Thus
Therefore the 79.8 miles per hours fast is the car going.