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what is the difference between density and relative density ?
How does a lactometer work ?
Why Newton's law of gravitation called universal law
what are the importance of universal law of gravitation??
Why does a plastic ball released under water come up to the surface of water?
List two factors on which buoyant force depends.
what happens to the gravitational force between two objects if
i) the mass of one object is doubled
ii) distance between two objects is doubled
iii) masses of both the objects are doubled
Two objects A and B are immersed in water. /the masses of the object are 200kg and 100kg respectively. If the weight of both the objects is 2m3, then --
a) Find the density of A and B
b) Find the ratio of densities of A and B.
c) Find the ratio of relative densities of B and A (B:A)
what is the difference between density and relative density of a substance
Why do objects float or sink when placed on the surface of liquid?
A coin sinks when placed on the surface of water.Give reasons.
what is the relationship between "G" and "g"?
For drinks during the day ,Peter has a cup of hot coffee at a temperature of 90 degree celsius and a cup of cold water ,with a minimum temperature of 5 degree celsius .THe cups are of identical type and size and volume of each drink is same .Peter leave the cup sitting in a room of temperature 20 degreee celsius
WHAT ARE THE TEMPERATURE OF COFFEE AND WATER LIKELY TO BE AFTER 10 MINUTES
EXPLAIN WITH REASON PLZ
Difference between thrust and pressure?
A ball thrown up vertically returns to the thrower after 6 s. Find
(a) the velocity with which it was thrown up,
(b) the maximum height it reaches, and
(c) its position after 4 s.
The gravitational force on a body of mass 60 kg is 588 N. If mass of earth is 6 x 1024 kg and radius of earth is 6.4 x 106m; find the value of G
A solid weighs 80g in air and 64g in water. Calculate its relative density. Also tell, when kept in water would the object float or sink.
which has more inertia man oR a child? give reasons for your answer.
What happens to the force between two objects, if
(i) the mass of one object is doubled?
(ii) the distance between the objects is doubled and tripled?
(iii) the masses of both objects are doubled?
Guys, it's urgent, plz answer them immediately...
Q1. A block weighing 1.0 kg is in the shape of a cube of length 10 cm. It is kept on a horizontal table. Find the pressure on the portion of the table where the block is kept. (ans. 1000Pa)
why a truck or a motorbus has wider tyres
An object is dropped from rest at a height of 150 m and simultaneously
another object is dropped from rest at a height 100 m. What is the difference
in their heights after 2 s if both the objects drop with same accelerations?
How does the difference in heights vary with time?
why the bottom of hydrometer is made heavy? give reason.
what are the characteristics of gravitational force.......????
a cylindrical block of radius r and mass m is lying on the table. if the radius is doubled and mass is tripled then what happens to pressure acting on the table
relative density of gold is 19.3.if the density of water is 1000kg/m3 ,what is density of gold in si unit?
1.if a body is compressed to half its previous volume,whay will happen to its density
2.three cubes of the same size made of iron,copper and lead are put in water.they sink.the buoyant force will be greatest on which cube?does it depend on density.
radius of an iron sphere is 0.21 cm If density of iron is 7.80g/cc calculate mass
A block of wood of density 0.70 gm/cm3 flaots in a mixture of water and alcohol of density 0.98 gm/cm3. What fraction of wood will be above the surface of mixture
A sharp knife is more effective than a blunt knife.why?
WHEN A PLANET MOVES AROUND THE SUN, ITS (A) AREAL VELOCITY IS CONSTANT (B) LINEAR VELOCITY IS CONSTANT
(C) ANGULAR VELOCITY IS CONSTANT (D) ALL THE VELOCITIES ARE CONSTANT
difference between mass and weight
why woodpecker has a long sharp beak?
WHAT IS THE S.I. UNIT OF UPTHRUST?
A body weighs 1 kg on the surface of the moon.If the mass of the moon is 7.4*10 power 22 kg,the radius pf moon is 1740 km and the gravitational constant 6.67*10 power -11 Nm power 2 *kg power -2,calculate a) the force acting on the i)body ii)moon b)the acceleration produced in the object c)the acceleration produced in the moon
what is the difference between thrust and force?
A flower pot drops from the edge of the roof of a multi storied building.Calculate the time taken by the pot cross to a particular distance AB of height 2.9 m , the upper point A being 19.6 m below the roof.
the acceleration due to gravity on a planet is 1.96m/s2 .If it is safe to jump from a height of 3m on the earth, the corresponding height of the planet will be ?
why is it difficult to hold a school bag having a strap made of thin & strong strip?
How archimedes principle is used to determine the purity of gold?
a stone is allowed to fall from the top of a tower 100m high and at the same time another stone is projected vertically upwards frome the ground with a velocity of 25ms-1 . calculate when and where the 2 stones will meet.
When an object is immersed into the fluid two forces act on the object in the vertically opposite directions. Name them and also write the factors on which the magnitude of these forces depends on.
A cylindrical block of radius r and mass m is lying on the table. If it's radius is doubled and mass is tripled then what happens to pressure acting on the table?
A body weighs 63 N on the surface of the earth. What is the gravitational force exerted on it due to the earth at a height equal to half the radius of the earth?
Name two substances whose density cannot be measured.
1) State Archimedes principle?
2) Give two applications of archimedes principle.
a stone is dropped from the edge of roof.
a]how long it take to fall 4.9m?
b]how fast does it move at the end of that fall?
c]how fast does it move at the end of 7.9m?
d]what is the acceleretion after 1 and 2 sec?
A solid weighs 80g in air, 68g in water and 60g in oil. Calculate the relative density of oil and solid.
difference between g and G .
how is the least count and the zero error of the spring balance is calculated?
name the factors affecting pressure
State the laws of floatation.
A cylindrical block of radius "r" and mass "m" is lying on the table. If its radius isdoubledand mass is tripled then what happens to pressure acting on the table.??
prove that if a body is thrown vertically upwards, the time of ascent is equal to the time of decent.
Q1 Give reasons:
A stone is thrown vertically upward with a velocity 40m/s and is caught back. Taking g=10m/s2.calculate the maximum height reached by the stone
Define one pascal.
At what height above the earth's surface would the value of acceleration due to gravity be half of what it is on the surface? Calculate.
A piece of iron of density 7.8 * 103kg/m3 and volume 100 cm3 is totally immersed in water. Calculate
(a) The weight of the iron piece in air
(b) The upthrust
(c) Apparent weight in water
A boat of mass 650kg floats on water. What volume of water does it displace?
A boy weighing 50 kg is standing on floor of lift .Find the weight when
a) lift moves up with uniform velocity b) lift moves down with an accleration of 4.9 ms-2
c) lift moves up with anacceleration of 4.9 ms-2 d) lift begins to fall freely under gravity
what are the applications of archimedes principle???
write the factor on which pressure depends
RELATIONSHIP BETWEEN SMALL g AND CAPITAL G
how to make model of lactometer on archimedes principle
why does buildings have wide foundations?
prove that if a body is thrown vertically upward , the time of ascent is equal to the time of descent.
Difference between fundamental quantity and derived quantity?
if the mass of the solid body is doubled it density ____________.
if the volume of the solid body is reduced to half, then its desity ________________.
the mass of a solid iron cube of side 4cm is to be determiined. four spring balances is available which is best suited and why ?
a) range 0 - 100g and least count 1g
b) range 0 - 100g, least count 5g
c) 0 - 1000g , least count is 10 g
d) 0- 1000g, least count 25g
Q - A boat floats on water with 3/4 th of its volume inside water, density of water is 10, 000 kg/m3 the density of the material of the boat is _____________________. How?
Q - density of a block of wood which floats on water with 0.1 of its volume avove water is _____________. How?
Explain last questions
the density of ice is 0.9 g/cm3. When it floats in water, what fraction of its volume will remain above surface?
During Freefall, what is the weight of a body? Give reason for your answer.
A sphere of mass 40 kg is attraced by a second sphere of mass 15 kg when their centers are 20 cm apart, with a force of 0.1 milligram weight. Calculate the value of gravitational constant.
The force on phonogram needle is 1.2 N.The point point has a circular cross section of radius 0.1mm.Calculate the pressureon the record in Pascal.
loaded test tube placed in pure milk sinks to a certain mark (M). Now some water is mixed with the milk. Will the test tube sink more or less? Explain.
A Piece of ice is placed gently on the surface of water in a glass so that when ice floats, the water comes up to the brim of the glass. what will happen to the level of water when the ice melts? will it overflow? (2) in the above case what will happen if instead of water the glass is filled with (a) with a liquid denser than water. (b) a liquid lighter than water.
a solid piece of lead experiences certain upthrust. the lead piece is then shaped into a hollow cube and placed in the same liquid. the upthrust acting on it :
a) increases
b) decreses
c) remains same
d) none of the above
please explain alongwith the answer!
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Syllabus
what is the difference between density and relative density ?
How does a lactometer work ?
Why Newton's law of gravitation called universal law
what are the importance of universal law of gravitation??
Why does a plastic ball released under water come up to the surface of water?
List two factors on which buoyant force depends.
what happens to the gravitational force between two objects if
i) the mass of one object is doubled
ii) distance between two objects is doubled
iii) masses of both the objects are doubled
Two objects A and B are immersed in water. /the masses of the object are 200kg and 100kg respectively. If the weight of both the objects is 2m3, then --
a) Find the density of A and B
b) Find the ratio of densities of A and B.
c) Find the ratio of relative densities of B and A (B:A)
what is the difference between density and relative density of a substance
Why do objects float or sink when placed on the surface of liquid?
A coin sinks when placed on the surface of water.Give reasons.
what is the relationship between "G" and "g"?
For drinks during the day ,Peter has a cup of hot coffee at a temperature of 90 degree celsius and a cup of cold water ,with a minimum temperature of 5 degree celsius .THe cups are of identical type and size and volume of each drink is same .Peter leave the cup sitting in a room of temperature 20 degreee celsius
WHAT ARE THE TEMPERATURE OF COFFEE AND WATER LIKELY TO BE AFTER 10 MINUTES
EXPLAIN WITH REASON PLZ
Difference between thrust and pressure?
for class 9 fast for revision
A ball thrown up vertically returns to the thrower after 6 s. Find
(a) the velocity with which it was thrown up,
(b) the maximum height it reaches, and
(c) its position after 4 s.
The gravitational force on a body of mass 60 kg is 588 N. If mass of earth is 6 x 1024 kg and radius of earth is 6.4 x 106m; find the value of G
A solid weighs 80g in air and 64g in water. Calculate its relative density. Also tell, when kept in water would the object float or sink.
which has more inertia man oR a child? give reasons for your answer.
What happens to the force between two objects, if
(i) the mass of one object is doubled?
(ii) the distance between the objects is doubled and tripled?
(iii) the masses of both objects are doubled?
Guys, it's urgent, plz answer them immediately...
Q1. A block weighing 1.0 kg is in the shape of a cube of length 10 cm. It is kept on a horizontal table. Find the pressure on the portion of the table where the block is kept. (ans. 1000Pa)
Q3. Calculate the mass of a body whose volume is 2 m3and density 0.52 g/cm3. (ans. 1040 kg)
Q4. A dining hall has dimensions 50m× 15m × 3.5m. Calculate the mass of air in the hall. Given, density of air =1.30kg/m3. (ans. 3412.5 kg)
Q5. A thread of mercury of 10.2 g is in a tube of uniform cross section 0.1cm3. Calculate the length of thread. The density of mercury is 13.6g/cm3. (ans. 7.5cm)
Q6. A cubical block of water is dipped completely in water. Each edge of the block is 1cm in length. Find the buoyant force acting on the block. (ans. 10-2N)
Q7. A body of mass 2.0 kg and density 8000 kg/m3is completely dipped in a liquid of density 800 kg/m3. Find the force of buoyancy on it. (ans. 2N)
Q8. A piece of iron of density 7.8 × 103kg/m3and volume 100 cm3is totally immersed in water. Calculate (a) the weight of the iron piece in air (b) the upthrust and (c) apparent weight in water. (ans. (a) 7.8N (b) 1N (c) 6.8 N)
Q9. A solid body of mass 150g and volume 250cm3is put in water. Will the body float or sink.
Q10. A solid of density 5000kg/m3weights 0.5 kg in air. It is completely immersed in water of density 1000kg/m3.
Q11. The mass of a block made of certain material is 13.5 kg and its volume is 15 × 10-3m3. Will the block float or sink in water. Give reason for your answer.
Q12. (a) What is the density of air in NTP? (b)What is the unit of relative density?
Q13. (a) When does a body sinks in a fluid?
(b)Why does a balloon filled with hydrogen gas rise up against gravity?
Q15. (a). A body weighs 10 N in air and 8 N when fully immersed in water. How much is the buoyant force acting on the body?
why a truck or a motorbus has wider tyres
An object is dropped from rest at a height of 150 m and simultaneously
another object is dropped from rest at a height 100 m. What is the difference
in their heights after 2 s if both the objects drop with same accelerations?
How does the difference in heights vary with time?
why the bottom of hydrometer is made heavy? give reason.
what are the characteristics of gravitational force.......????
a cylindrical block of radius r and mass m is lying on the table. if the radius is doubled and mass is tripled then what happens to pressure acting on the table
relative density of gold is 19.3.if the density of water is 1000kg/m3 ,what is density of gold in si unit?
1.if a body is compressed to half its previous volume,whay will happen to its density
2.three cubes of the same size made of iron,copper and lead are put in water.they sink.the buoyant force will be greatest on which cube?does it depend on density.
radius of an iron sphere is 0.21 cm If density of iron is 7.80g/cc calculate mass
A block of wood of density 0.70 gm/cm3 flaots in a mixture of water and alcohol of density 0.98 gm/cm3. What fraction of wood will be above the surface of mixture
A sharp knife is more effective than a blunt knife.why?
WHEN A PLANET MOVES AROUND THE SUN, ITS
(A) AREAL VELOCITY IS CONSTANT
(B) LINEAR VELOCITY IS CONSTANT
(C) ANGULAR VELOCITY IS CONSTANT
(D) ALL THE VELOCITIES ARE CONSTANT
difference between mass and weight
why woodpecker has a long sharp beak?
WHAT IS THE S.I. UNIT OF UPTHRUST?
A body weighs 1 kg on the surface of the moon.If the mass of the moon is 7.4*10 power 22 kg,the radius pf moon is 1740 km and the gravitational constant 6.67*10 power -11 Nm power 2 *kg power -2,calculate a) the force acting on the i)body ii)moon b)the acceleration produced in the object c)the acceleration produced in the moon
what is the difference between thrust and force?
A flower pot drops from the edge of the roof of a multi storied building.Calculate the time taken by the pot cross to a particular distance AB of height 2.9 m , the upper point A being 19.6 m below the roof.
the acceleration due to gravity on a planet is 1.96m/s2 .If it is safe to jump from a height of 3m on the earth, the corresponding height of the planet will be ?
why is it difficult to hold a school bag having a strap made of thin & strong strip?
How archimedes principle is used to determine the purity of gold?
a stone is allowed to fall from the top of a tower 100m high and at the same time another stone is projected vertically upwards frome the ground with a velocity of 25ms-1 . calculate when and where the 2 stones will meet.
When an object is immersed into the fluid two forces act on the object in the vertically opposite directions. Name them and also write the factors on which the magnitude of these forces depends on.
A cylindrical block of radius r and mass m is lying on the table. If it's radius is doubled and mass is tripled then what happens to pressure acting on the table?
A body weighs 63 N on the surface of the earth. What is the gravitational force exerted on it due to the earth at a height equal to half the radius of the earth?
(b) when a stone is thrown vertically upward its velocity continuously discarded. why?
(c) give an example of a motion in which average velocity is zero, but average speed is not zero.
Name two substances whose density cannot be measured.
Q. An object is dropped from the top of a multistorey building. After 2 Seconds, what will be the magnitude of the velocity of an object ?
(take g=9.8 m/s2)
1) State Archimedes principle?
2) Give two applications of archimedes principle.
a stone is dropped from the edge of roof.
a]how long it take to fall 4.9m?
b]how fast does it move at the end of that fall?
c]how fast does it move at the end of 7.9m?
d]what is the acceleretion after 1 and 2 sec?
A solid weighs 80g in air, 68g in water and 60g in oil. Calculate the relative density of oil and solid.
difference between g and G .
how is the least count and the zero error of the spring balance is calculated?
(a) Length (b) Mass (c) Volume (d) Time
19. Which one of the following is not a derived quantity
(a) density (b) mass (c) volume (d) speed
name the factors affecting pressure
State the laws of floatation.
A cylindrical block of radius "r" and mass "m" is lying on the table. If its radius isdoubledand mass is tripled then what happens to pressure acting on the table.??
prove that if a body is thrown vertically upwards, the time of ascent is equal to the time of decent.
Q1 Give reasons:
A stone is thrown vertically upward with a velocity 40m/s and is caught back. Taking g=10m/s2.calculate the maximum height reached by the stone
Define one pascal.
At what height above the earth's surface would the value of acceleration due to gravity be half of what it is on the surface? Calculate.
A piece of iron of density 7.8 * 103kg/m3 and volume 100 cm3 is totally immersed in water. Calculate
(a) The weight of the iron piece in air
(b) The upthrust
(c) Apparent weight in water
A boat of mass 650kg floats on water. What volume of water does it displace?
A boy weighing 50 kg is standing on floor of lift .Find the weight when
a) lift moves up with uniform velocity b) lift moves down with an accleration of 4.9 ms-2
c) lift moves up with anacceleration of 4.9 ms-2 d) lift begins to fall freely under gravity
what are the applications of archimedes principle???
write the factor on which pressure depends
RELATIONSHIP BETWEEN SMALL g AND CAPITAL G
1) If area is doubled?
b) If area is halved ?
how to make model of lactometer on archimedes principle
Explain why the pin causes more pain in man's thumb than in his finger
why does buildings have wide foundations?
prove that if a body is thrown vertically upward , the time of ascent is equal to the time of descent.
Difference between fundamental quantity and derived quantity?
if the mass of the solid body is doubled it density ____________.
if the volume of the solid body is reduced to half, then its desity ________________.
the mass of a solid iron cube of side 4cm is to be determiined. four spring balances is available which is best suited and why ?
a) range 0 - 100g and least count 1g
b) range 0 - 100g, least count 5g
c) 0 - 1000g , least count is 10 g
d) 0- 1000g, least count 25g
Q - A boat floats on water with 3/4 th of its volume inside water, density of water is 10, 000 kg/m3 the density of the material of the boat is _____________________. How?
Q - density of a block of wood which floats on water with 0.1 of its volume avove water is _____________. How?
Explain last questions
the density of ice is 0.9 g/cm3. When it floats in water, what fraction of its volume will remain above surface?
During Freefall, what is the weight of a body? Give reason for your answer.
A sphere of mass 40 kg is attraced by a second sphere of mass 15 kg when their centers are 20 cm apart, with a force of 0.1 milligram weight. Calculate the value of gravitational constant.
The force on phonogram needle is 1.2 N.The point point has a circular cross section of radius 0.1mm.Calculate the pressureon the record in Pascal.
loaded test tube placed in pure milk sinks to a certain mark (M). Now some water is mixed with the milk. Will the test tube sink more or less? Explain.
A Piece of ice is placed gently on the surface of water in a glass so that when ice floats, the water comes up to the brim of the glass. what will happen to the level of water when the ice melts? will it overflow? (2) in the above case what will happen if instead of water the glass is filled with (a) with a liquid denser than water. (b) a liquid lighter than water.
a solid piece of lead experiences certain upthrust. the lead piece is then shaped into a hollow cube and placed in the same liquid. the upthrust acting on it :
a) increases
b) decreses
c) remains same
d) none of the above
please explain alongwith the answer!