Answer:
A) a = 73.304 rad/s²
B) Δθ = 3665.2 rad
Explanation:
A) From Newton's first equation of motion, we can say that;
a = (ω - ω_o)/t. We are given that the centrifuge spins at a maximum rate of 7000rpm.
Let's convert to rad/s = 7000 × 2π/60 = 733.04 rad/s
Thus change in angular velocity = (ω - ω_o) = 733.04 - 0 = 733.04 rad/s
We are given; t = 10 s
Thus;
a = 733.04/10
a = 73.304 rad/s²
B) From Newton's third equation of motion, we can say that;
ω² = ω_o² + 2aΔθ
Where Δθ is angular displacement
Making Δθ the subject;
Δθ = (ω² - ω_o²)/2a
At this point, ω = 0 rad/s while ω_o = 733.04 rad/s
Thus;
Δθ = (0² - 733.04²)/(2 × 73.304)
Δθ = -537347.6416/146.608
Δθ = - 3665.2 rad
We will take the absolute value.
Thus, Δθ = 3665.2 rad
Answer:
Velocity of airplane is 500 km/h
Velocity of wind is 40 km/h
Explanation:
= Velocity of airplane in still air
= Velocity of wind
Time taken by plane to travel 1150 km against the wind is 2.5 hours
Time taken by plane to travel 450 km against the wind is 50 minutes = 50/60 hours
Subtracting the two equations we get
Applying the value of velocity of wind to the first equation
∴ Velocity of airplane in still air is 500 km/h and Velocity of wind is 40 km/h
Wavelength = velocity/frequency
wavelength = v/f
v= 13km/s = change this to m/s = 13000m/s
f= 14Hz
wavelength = 13000m/s÷14Hz =928.7 m
Answer:
Explanation:
Ignoring friction, the initial kinetic energy will convert to maximum potential energy at its highest point.
PE = KE
mgh = ½mv²
h = v²/2g
h = 36.4²/ (2(9.81))
h = 67.53109...
h = 67.53 m
Answer:
12 m/s
Explanation:
Speed is distance moved per unit time and expressed as
S=d/t
S is speed, d is distance and t is time.
When at rest for five minutes, distance moved is zero hence speed is 0/5=0 m/s
When having moved 120 m for 5 s then speed is
S=120/5=24 m/s
Average speed is the average of these two speeda
Average speed=(24+0)÷2=24/2=12 m/s
Therefore, average speed is 12 m/s
