Answer:
Pressure applied to the needle is 7528 Pa
Explanation:
As we know by poiseuille's law of flow of liquid through a cylindrical pipe
the rate of flow through the pipe is given as

now we know that

radius = 0.2 mm
Length = 6.32 cm

now we have



now we have


Answer:
Explanation:
Given that,
Initial angular velocity is 0
ωo=0rad/s
It has angular velocity of 11rev/sec
ωi=11rev/sec
1rev=2πrad
Then, wi=11rev/sec ×2πrad
wi=22πrad/sec
And after 30 revolution
θ=30revolution
θ=30×2πrad
θ=60πrad
Final angular velocity is
ωf=18rev/sec
ωf=18×2πrad/sec
ωf=36πrad/sec
a. Angular acceleration(α)
Then, angular acceleration is given as
wf²=wi²+2αθ
(36π)²=(22π)²+2α×60π
(36π)²-(22π)²=120πα
Then, 120πα = 8014.119
α=8014.119/120π
α=21.26 rad/s²
Let. convert to revolution /sec²
α=21.26/2π
α=3.38rev/sec
b. Time Taken to complete 30revolution
θ=60πrad
∆θ= ½(wf+wi)•t
60π=½(36π+22π)t
60π×2=58πt
Then, t=120π/58π
t=2.07seconds
c. Time to reach 11rev/sec
wf=wo+αt
22π=0+21.26t
22π=21.26t
Then, t=22π/21.26
t=3.251seconds
d. Number of revolution to get to 11rev/s
∆θ= ½(wf+wo)•t
∆θ= ½(0+11)•3.251
∆θ= ½(11)•3.251
∆θ= 17.88rev.
Answer:

direction is Horizontal
Explanation:
As we know that the string is horizontal here
so the tension force in the string is due to electrostatic force on it
now we will have

so here the force is tension force on it


now we have


direction is Horizontal
Answer:v=3.28 m/s
Explanation:
Given
mass of rock 
diameter of circle 
radius 
At highest Point

At highest Point N=0 because mass is just balanced by centripetal Force
thus 




Answer:
temperature measures heat - the unit is Celsius - and it is measured with a thermometer.
length is measuring how long, tall, or wide something is - the base unit it metres - and it is measured with a ruler or a metre stick
volume is measuring the quantity of a three dimensional space - the unit is cubic centimetre - you find volume by taking the measurements with a ruler
mass is measuring how much space something takes up/ weight - unit is the gram - you use a scale