Home
Class 11
PHYSICS
A glass plate of lengthh 10 cm, breadth ...

A glass plate of lengthh `10 cm`, breadth `1.54 cm` and thickness `0.20 cm` weight `8.2 g` in air. It is held vertically with the long side horizontal and the lower half under water. Find the apparent weight of the plate. Surface tension of water `=7.3xx10^(-2)N//m` and `=9.8ms^(-12)`

Text Solution

Verified by Experts

The force acting on the plate are
a. Weight of plate (`mg`) acting vertically downward.
b. force of surface tension (`TL`) acting vertically downward.
c. Upthrust.

Weight of glass plate `=8.2g=8.2xx10^(-3)kg`
Total length of plate is contact in with water surface is
`l=2(10+0.2)cm=20.4xx10^(-2)m`
Therefore downard pull upon the plate due to surface tension
`TL=7.xx10^(-2)xx20.4xx10^(2)=14.892xx10^(-3)N`
`=(14.892xx10^(-3))/9.8=1.5196xx10^(-3)kgwt`
Volume of plate immersed in water is
`v=10xx1/2(1.54)xx0.2=1.54.10^(-6)m^(3)`
Therefore, upthrust `=vsigmag=1.54xx10^(-6)x10^(3)xx9.8N`
`=(1.54xx10^(-3)xx9.8)/9.8kgwt=1.54xx10^(-3)kgwt`
Therefore apparent weight of plate in water `=` weight of plate in air `+` Force of surface tension `-`Upthrust
`=8.2xx10^(-3)+1.5196xx10^(-3)-1.54xx10^(-3)`
`=8.1796xx10^(-6)kgw=8.1796kgwt`
Promotional Banner

Topper's Solved these Questions

  • PROPERTIES OF SOLIDS AND FLUIDS

    CENGAGE PHYSICS|Exercise Exercise 5.1|12 Videos

  • PROPERTIES OF SOLIDS AND FLUIDS

    CENGAGE PHYSICS|Exercise Exercise 5.2|6 Videos

  • PROPERTIES OF SOLIDS AND FLUIDS

    CENGAGE PHYSICS|Exercise INTEGER_TYPE|2 Videos

  • NEWTON'S LAWS OF MOTION 2

    CENGAGE PHYSICS|Exercise Integer type|1 Videos

  • RIGID BODY DYNAMICS 1

    CENGAGE PHYSICS|Exercise Integer|11 Videos

Similar Questions

Explore conceptually related problems

A glass plate of length 10 cm , breadth 1.54 cm and thickness 0.20 cm weights 8.2 gm in air, It is held vertically with the long side horizontal and the lower half under water. Find the apperent weight of the plate. Surface tension of water = 73 "dyne" per cm, g = 980 "cm"//"sec"^(2)

A glass plate of length 10 cm., breadth 1.5 cm. and thickness 0.2 cm., weighs 8.2 gm. In air. It is held vertically with long side horizontal and half the plate immersed in water. What will be its apperent weight ? Surface tension of water = 73 dynes//cm.

A glass plate of length 10 cm, breadth 4 cm, and the thickness 0.4cm , weighs 20g in air. It is held vertically with long side horizontal and half the plate immersed in water. What will be its apparent weight? Surface tension of water = 70 dyn e//cm .

A glass plate of length 0.1 m , breadth 15 xx 10^(3) m and thickness 2 xx 10^(-3)m weighs 8 xx 10^(-3) kg in air, it is held vertically with its longer side horizontal and its lower half immersed in water. If the surfaces tension of water is 72 xx 10^(-3) N//m , the apparent weight of the plate is 79.4 lambda xx 10^(-3) N . Then find lambda

A square glass plate of length 10 cm and thickness 0.4 cm, weight 40 g in air. It is held vertically such that its lower edge rests on water surface. What is the apparent weight of glass plate now? (Given surface tension of water = 0.073 N m^(-1) )

A clean glass plate of length 9.8 cm , breadth 4 cm an thicness 0.2 cm is suspended vertically with its long side horizontal and with half the side immersed. Pull due to suface tension will be (S.T.=0.07N//m )

A steel needle of length 5 cm can stay aflot on water . Find the weight of the needle . [ Surface tension of water = 0.07 N/m]

A glass plate of length 8cm, breadth 3 cm and thickness 0.2cm weighs 15 g in air. What will the apparent weight of the plate if it is half immersed vertically in water its long side held hrizontal? Take, Surface tension of water =70 dyne/cm

A glass capillary of radius 0.4 mm is inclined at 60^(@) with the vertical in water. Find the length of water in the capillary tube. (Given, surface tension of water = 7 xx 10^(-2) N^(-1) ).