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a barometer kept in an elevator reads 76cm when the elevator is accelerating upwards . the most likely pressure inside the elevator (in mm of Hg) is
(1) 74
(2) 75
(3) 76
(4) 77
ans: 77 reason???
which chapters come under the topic mechanics and electrodynamics in our 11 thand 12 th syllabus
By sucking through a straw , a boy can reduce the pressure in his lungs to 750mm of Hg (density= 13.6 g/cc) using a straw he can drink water from a max depth of
ans: 13.6
??
an open U-tube contains mercury . when 13.6 cm of water is poured into one of the arms of the tube , then the mercury rise in the othe arm from its initial level is
ans: 0.5cm
why not 1cm
work done in increasing the size of soap film from 10cm x6cm to 10cmx 11cm is 3x10^-4 J
the surface tension of the film is
ans:3x10^-2 N/m
An open glass tube is immersed in mercury in such a way that a length of 8cm extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46cm. What will be the length of air column above mercury in the tube now? (atm pressure= 76 cm of Hg)
The level of blood in bottle used to give blood to a patient is 1.3 m high above the needle which is 3 cm in length and has internal diameter of 0.36 mm. If 4.5 cm^3 of blood is passing through the needle per minute, calculate the viscosity of blood. The density of blood is 1020 kg/m^3.
Ignore fall in level of blood in the bottle.
Water flows through a horizontal tube of variable crosssection. The area of crosssection at A and B are 4 mm2 and 2 mm2 respectvely. If 1 cc of water enters per second through A, find (a) the speed of water at A, (b) the speed of water at B and (C) the pressure difference PA - PB
Glycerine flows through a conical section of a pipe, with the cross sectional area at its two ends as 1 m2 and 4 m2. The pressure drop across the ends of a pipe is 10 N/m2. Calculate the velocity of at narrow end.
A rain drop of radius r falls in air with a terminal velocity v. What is the terminal velocity of a rain drop of radius 3r ?
A wire is stretched by a force such that its length becomes double. How will the Youngs modulus of the wire be affected?explain in detail.
if S is the stress and Y is youngs modulus of the material of wire ,what is the energy stored in the wire per unit volume in terms of S and Y?PLEASE EXPLAIN IN DETAIL WITH DIAGRAM.
show that bernoulli's equation is same as theequation dueto pascal's law in the presence of gravity if a liquid or gas is a rest.
The cylindrical cube of a spray pump has a cross-section of 8cm2. One end of which has 40 holes. Each of diameter 1mm. If the liquid flows inside the tube is 1.25 m/minute. What is the speed of ejection of the liquid through the holes.
hair of shaving brush spreads out when dipped in h2o an sticks out when taken out.
small mercury drops are sperical while bigger ones tends to expand.
olive oil spreads on cold h2o bt reman as drop in hot h2o.
A Hydraulic presswith a larger piston of diameter 30cm at a height 1m above the smaller piston of diameter 5cm is present.The mass on the Smaller piston is 10kg . What is the force exerted on the Load by the larger piston . (Density of Oil = 750kgm^-3
Q. What would be the gauge pressure inside an air bubble of 0.2mm radius situated just below the surface of water ? (Surface Tension of water = 0.07 N/m)
Pls explain me this questionOn heating water, bubbles being formed at the bottom of the vessel detach and rise. Consider the bubbles to be spheres of radiusRand making a circular contact of radiusrwith the bottom of the vessel. IfrR, and the surface tension of water isT, value ofrjust before the bubbles detach is(density of water isρw)
how is the mechanical advantage of a hydraulic lift A2/A1, where A2 and A1 are the area of cross section of the larger and smaller piston respectively ?
Explain how does a body attain terminal velocity when it is dropped from rest in a viscous medium. Define terminal velocityderive an expression for it.Why air bubble in medium move in what direction?
A liquid stands at the same level in Utube at rest.If A is the area of cross section and g is the acceleration due to gravity .What will be the difference in height h of the liquid in the two limbs of U tube when th e system is given an acceleration towards right
Define surface energy in mathematical terms.
if its surface tension * area (surface tension = surface energy per unit area)
then y is it written in NCERT book that surface energy is surface tension per unit area.
1--one end of a u-tube of a uniform bore (area A) containing mercury is connected to a sanction pump . because of it the level of liquid of density p falls in one limb by x when the pump is removed, the restoring force in the other limb is
Ans--2xpAg
If T is the surface tension of soap solution, the amount of work done in blowing a soap bubble from a diameter D to 2D ??
Molecular motion shows itself as
Why is pressure on a concave side of a liquid drop or bubble more than that on its convex side
When air is blown in between two balls suspended close to each other , they are attracted towards each other. Why? PLEASE EXPLAIN IN DETAIL WITH DIAGRAM.
What is the pressure inside the drop of mercury of radius 3.00 mm at room temperature? Surface tension of mercury at that temperature (20°C) is 4.65 × 10–1 N m–1. The atmospheric pressure is 1.01 × 105 Pa. Also give the excess pressure inside the drop.
Q)what height of water column would balance the atmospheric pressure in a water barometer?
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Syllabus
a barometer kept in an elevator reads 76cm when the elevator is accelerating upwards . the most likely pressure inside the elevator (in mm of Hg) is
(1) 74
(2) 75
(3) 76
(4) 77
ans: 77 reason???
which chapters come under the topic mechanics and electrodynamics in our 11 thand 12 th syllabus
By sucking through a straw , a boy can reduce the pressure in his lungs to 750mm of Hg (density= 13.6 g/cc) using a straw he can drink water from a max depth of
ans: 13.6
??
an open U-tube contains mercury . when 13.6 cm of water is poured into one of the arms of the tube , then the mercury rise in the othe arm from its initial level is
ans: 0.5cm
why not 1cm
work done in increasing the size of soap film from 10cm x6cm to 10cmx 11cm is 3x10^-4 J
the surface tension of the film is
ans:3x10^-2 N/m
2. there is a hole in the bottom of tank having water. if total pressure at bottom is 3 atm (1atm= 105 N/m2); then the velocity of water flowing from the hole is :
a. root(400)m/s b. root(600) m/s.
An open glass tube is immersed in mercury in such a way that a length of 8cm extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46cm. What will be the length of air column above mercury in the tube now? (atm pressure= 76 cm of Hg)
The level of blood in bottle used to give blood to a patient is 1.3 m high above the needle which is 3 cm in length and has internal diameter of 0.36 mm. If 4.5 cm^3 of blood is passing through the needle per minute, calculate the viscosity of blood. The density of blood is 1020 kg/m^3.
Ignore fall in level of blood in the bottle.
Water flows through a horizontal tube of variable crosssection. The area of crosssection at A and B are 4 mm2 and 2 mm2 respectvely. If 1 cc of water enters per second through A, find (a) the speed of water at A, (b) the speed of water at B and (C) the pressure difference PA - PB
Glycerine flows through a conical section of a pipe, with the cross sectional area at its two ends as 1 m2 and 4 m2. The pressure drop across the ends of a pipe is 10 N/m2. Calculate the velocity of at narrow end.
A rain drop of radius r falls in air with a terminal velocity v. What is the terminal velocity of a rain drop of radius 3r ?
A wire is stretched by a force such that its length becomes double. How will the Youngs modulus of the wire be affected?explain in detail.
1. 5/11
2. 7/11
3. 11/24
4. 11/36
if S is the stress and Y is youngs modulus of the material of wire ,what is the energy stored in the wire per unit volume in terms of S and Y?PLEASE EXPLAIN IN DETAIL WITH DIAGRAM.
show that bernoulli's equation is same as theequation dueto pascal's law in the presence of gravity if a liquid or gas is a rest.
The cylindrical cube of a spray pump has a cross-section of 8cm2. One end of which has 40 holes. Each of diameter 1mm. If the liquid flows inside the tube is 1.25 m/minute. What is the speed of ejection of the liquid through the holes.
hair of shaving brush spreads out when dipped in h2o an sticks out when taken out.
small mercury drops are sperical while bigger ones tends to expand.
olive oil spreads on cold h2o bt reman as drop in hot h2o.
A Hydraulic presswith a larger piston of diameter 30cm at a height 1m above the smaller piston of diameter 5cm is present.The mass on the Smaller piston is 10kg . What is the force exerted on the Load by the larger piston . (Density of Oil = 750kgm^-3
cosX= g/a
tanX=a/g
sinX=a/g
tanX=g/a
Q. What would be the gauge pressure inside an air bubble of 0.2mm radius situated just below the surface of water ? (Surface Tension of water = 0.07 N/m)
Pls explain me this questionOn heating water, bubbles being formed at the bottom of the vessel detach and rise. Consider the bubbles to be spheres of radiusRand making a circular contact of radiusrwith the bottom of the vessel. IfrR, and the surface tension of water isT, value ofrjust before the bubbles detach is(density of water isρw)
how is the mechanical advantage of a hydraulic lift A2/A1, where A2 and A1 are the area of cross section of the larger and smaller piston respectively ?
Explain how does a body attain terminal velocity when it is dropped from rest in a viscous medium. Define terminal velocityderive an expression for it.Why air bubble in medium move in what direction?
A liquid stands at the same level in Utube at rest.If A is the area of cross section and g is the acceleration due to gravity .What will be the difference in height h of the liquid in the two limbs of U tube when th e system is given an acceleration towards right
Define surface energy in mathematical terms.
if its surface tension * area (surface tension = surface energy per unit area)
then y is it written in NCERT book that surface energy is surface tension per unit area.
A)water in A increases B)water in A decreases C)Liquid in B decreases
D)Liquid in B increases E)water in A and liquid in B remains unaltered
1--one end of a u-tube of a uniform bore (area A) containing mercury is connected to a sanction pump . because of it the level of liquid of density p falls in one limb by x when the pump is removed, the restoring force in the other limb is
Ans--2xpAg
If T is the surface tension of soap solution, the amount of work done in blowing a soap bubble from a diameter D to 2D ??
Molecular motion shows itself as
A. Temperature B. Internal Energy C. Friction D. Viscosity( surface tension = T , density = rho ), find capillary rise h .
Also explain the significance of [ ( d2- d1) << d1 ,d2) ]
Why is pressure on a concave side of a liquid drop or bubble more than that on its convex side
When air is blown in between two balls suspended close to each other , they are attracted towards each other. Why? PLEASE EXPLAIN IN DETAIL WITH DIAGRAM.
What is the pressure inside the drop of mercury of radius 3.00 mm at room temperature? Surface tension of mercury at that temperature (20°C) is 4.65 × 10–1 N m–1. The atmospheric pressure is 1.01 × 105 Pa. Also give the excess pressure inside the drop.
Q)what height of water column would balance the atmospheric pressure in a water barometer?