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Assertion The formula connecting u, v an...

Assertion The formula connecting u, v and f for a spherical mirror is valid only for mirrors sizes which are very small compared to their radii of curvature.
Reason Laws of reflection are stricity valid for plane surface, but not for large spherical.

A

If both Assertion and Reason are true and Reason is correct explanation of Assertion.

B

If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

C

If Assertion is true but Reason is false.

D

If both Assertion and Reason are false.

Text Solution

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The correct Answer is:
A
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In each of the questions, assertion(A) is given by corresponding statement of reason (R) of the statemens. Mark the correct answer. Q. Statement I: The formula connecting u,v and f for a spherical mirror is valid only for mirrors whose sizes are very small compared to their radii of curvature. Statement II: Laws of reflection are strictly valid for plane surfaces, but not for large spherical surfaces.

STATEMENT-1 The formula connecting u,v and f for a spherical mirrors whose sizes are very small compared to their radii of curvature. STATEMENT-2 Laws of reflection are strictly valid for plane surfaces, but not for large spherical surfaces.

Huygen was the figure scientist who proposed the idea of wave theory of light he said that the light propagates in form of wavelengths. A wavefront is a imaginary surface of every point of which waves are in the same. phase. For example the wavefront for a point source of light is collection of concentric spheres which have centre at the origin w_(1) is a wavefront w_(2) is another wavefront. The radius of the wavefront at time 't' is 'ct' in thic case where 'c' is the speed of light the direction of propagation of light is perpendicular to the surface of the wavelength. the wavefronts are plane wavefronts in case of a parallel beam of light. Huygen also said that every point of the wavefront acts as the source of secondary wavelets. The tangent drawn to all secondary wavelets at a time is the new wavefront at that time. The wavelets are to be considered only in the forward direction (i.e., the direction of propagation of light) and not in the reverse direction if a wavefront w_(1) and draw spheres of radius 'cDeltat' they are called secondary wavelets. Draw a surface w_(2) which is tangential to all these secondary wavelets w_(2) is the wavefront at time t+Deltat Huygen proved the laws of reflection and laws of refraction using concept of wavefront. Q. Plane are incident on a spherical mirror as shown in the figure. the reflected wavefronts will be

Huygen was the figure scientist who proposed the idea of wave theory of light he said that the light propagates in form of wavelengths. A wavefront is a imaginary surface of every point of which waves are in the same. phase. For example the wavefront for a point source of light is collection of concentric spheres which have centre at the origin w_(1) is a wavefront w_(2) is another wavefront. The radius of the wavefront at time 't' is 'ct' in thic case where 'c' is the speed of light the direction of propagation of light is perpendicular to the surface of the wavelength. the wavefronts are plane wavefronts in case of a parallel beam of light. Huygen also said that every point of the wavefront acts as the source of secondary wavelets. The tangent drawn to all secondary wavelets at a time is the new wavefront at that time. The wavelets are to be considered only in the forward direction (i.e., the direction of propagation of light) and not in the reverse direction if a wavefront w_(1) and draw spheres of radius 'cDeltat' they are called secondary wavelets. Draw a surface w_(2) which is tangential to all these secondary wavelets w_(2) is the wavefront at time t+Deltat Huygen proved the laws of reflection and laws of refraction using concept of wavefront. Q. Plane are incident on a spherical mirror as shown in the figure. the reflected wavefronts will be

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When an object moves through a fluid, as when a ball falls through air or a glass sphere falls through water te fluid exerts a viscous foce F on the object this force tends to slow the object for a small sphere of radius r moving is given by stoke's law, F_(w)=6pietarv . in this formula eta in the coefficient of viscosity of the fluid which is the proportionality constant that determines how much tangential force is required to move a fluid layer at a constant speed v, when the layer has an area A and is located a perpendicular distance z from and immobile surface. the magnitude of the force is given by F=etaAv//z . For a viscous fluid to move from location 2 to location 1 along 2 must exceed that at location 1, poiseuilles's law given the volumes flow rate Q that results from such a pressure difference P_(2)-P_(1) . The flow rate of expressed by the formula Q=(piR^(4)(P_(2)-P_(1)))/(8etaL) poiseuille's law remains valid as long as the fluid flow is laminar. For a sfficiently high speed however the flow becomes turbulent flow is laminar as long as the reynolds number is less than approximately 2000. This number is given by the formula R_(e)=(2overline(v)rhoR)/(eta) In which overline(v) is the average speed rho is the density eta is the coefficient of viscosity of the fluid and R is the radius of the pipe. Take the density of water to be rho=1000kg//m^(3) Q. Calculate the highest average speed that blood (rho~~1000kg//m^(3) ) could have and still remain in laminar flow when it flows through the arorta (R=8xx10^(-3)m ) Take the coeffiicient of viscosity of blood to be 4xx10^(-3)Pa-s

When an object moves through a fluid, as when a ball falls through air or a glass sphere falls through water te fluid exerts a viscous foce F on the object this force tends to slow the object for a small sphere of radius r moving is given by stoke's law, F_(w)=6pietarv . in this formula eta in the coefficient of viscosity of the fluid which is the proportionality constant that determines how much tangential force is required to move a fluid layer at a constant speed v, when the layer has an area A and is located a perpendicular distance z from and immobile surface. the magnitude of the force is given by F=etaAv//z . For a viscous fluid to move from location 2 to location 1 along 2 must exceed that at location 1, poiseuilles's law given the volumes flow rate Q that results from such a pressure difference P_(2)-P_(1) . The flow rate of expressed by the formula Q=(piR^(4)(P_(2)-P_(1)))/(8etaL) poiseuille's law remains valid as long as the fluid flow is laminar. For a sfficiently high speed however the flow becomes turbulent flow is laminar as long as the reynolds number is less than approximately 2000. This number is given by the formula R_(e)=(2overline(v)rhoR)/(eta) In which overline(v) is the average speed rho is the density eta is the coefficient of viscosity of the fluid and R is the radius of the pipe. Take the density of water to be rho=1000kg//m^(3) Q. What is the viscous force on a glass sphere of radius r=1mm falling through water (eta=1xx10^(-3)Pa-s) when the sphere has speed of 3m/s?

When an object moves through a fluid, as when a ball falls through air or a glass sphere falls through water te fluid exerts a viscous foce F on the object this force tends to slow the object for a small sphere of radius r moving is given by stoke's law, F_(w)=6pietarv . in this formula eta in the coefficient of viscosity of the fluid which is the proportionality constant that determines how much tangential force is required to move a fluid layer at a constant speed v, when the layer has an area A and is located a perpendicular distance z from and immobile surface. the magnitude of the force is given by F=etaAv//z . For a viscous fluid to move from location 2 to location 1 along 2 must exceed that at location 1, poiseuilles's law given the volumes flow rate Q that results from such a pressure difference P_(2)-P_(1) . The flow rate of expressed by the formula Q=(piR^(4)(P_(2)-P_(1)))/(8etaL) poiseuille's law remains valid as long as the fluid flow is laminar. For a sfficiently high speed however the flow becomes turbulent flow is laminar as long as the reynolds number is less than approximately 2000. This number is given by the formula R_(e)=(2overline(v)rhoR)/(eta) In which overline(v) is the average speed rho is the density eta is the coefficient of viscosity of the fluid and R is the radius of the pipe. Take the density of water to be rho=1000kg//m^(3) Q. If the sphere in previous question has mass of 1xx10^(-5)kg what is its terminal velocity when falling through water? (eta=1xx10^(-3)Pa-s) A. 1.3m/s B. 3.4m/s C. 5.2m/s D. 6.5m/s

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