Answer:
230
Explanation:
= Rotational speed = 3600 rad/s
I = Moment of inertia = 6 kgm²
m = Mass of flywheel = 1500 kg
v = Velocity = 15 m/s
The kinetic energy of flywheel is given by
Energy used in one acceleration
Number of accelerations would be given by
So the number of complete accelerations is 230
Answer:
Explanation:
Impulse = change in momentum
mv - mu , v and u are final and initial velocity during impact at surface
For downward motion of baseball
v² = u² + 2gh₁
= 2 x 9.8 x 2.25
v = 6.64 m / s
It becomes initial velocity during impact .
For body going upwards
v² = u² - 2gh₂
u² = 2 x 9.8 x 1.38
u = 5.2 m / s
This becomes final velocity after impact
change in momentum
m ( final velocity - initial velocity )
.49 ( 5.2 - 6.64 )
= .7056 N.s.
Impulse by floor in upward direction
= .7056 N.s
Answer:
the correct answer is E
A graph of the cart's maximum speed squared as a function of x^3
Explanation:
For this exercise let's use Newton's second law
F = m a
force has the form
F = k x²
and acceleration is related to velocity
a = dv / dt
Let's use the chain rule or L'Hospital
a = dv /dx dx/dt
a = dv /dx v
let's substitute
k x² = m v dv / dx
k /m x² dx = v dv
we integrate
k /m x³ /3 = v² / 2
v² = (2k /3m) x³
This is the expression for the variation of the speed as a function of the position, to make a linear graph realism the changes of variable
y = v²
x´ = x³
y = (2k/3m) x´
if we graph y vs x 'we have a linear graph whose slope is
m = 2k / 3m
By reviewing the different answers, the correct answer is E
Answer:
Explanation:
position of centre of mass of door from surface of water
= 10 + 1.1 / 2
= 10.55 m
Pressure on centre of mass
atmospheric pressure + pressure due to water column
10 ⁵ + hdg
= 10⁵ + 10.55 x 1000 x 9.8
= 2.0339 x 10⁵ Pa
the net force acting on the door (normal to its surface)
= pressure at the centre x area of the door
= .9 x 1.1 x 2.0339 x 10⁵
= 2.01356 x 10⁵ N
pressure centre will be at 10.55 m below the surface.
When the car is filled with air or it is filled with water , in both the cases pressure centre will lie at the centre of the car .
