282355 A convex lens has power \(P\). It is cut into two halves along its principal axis. Further one piece (out of the two halves) is cut into two halves perpendicular to the principal axis (as shown in figures). Choose the incorrect options for the reported pieces.

282356 A convex lens focuses an object \(20 \mathrm{~cm}\) from it on a screen placed \(5 \mathrm{~cm}\) away from it. A glass plate (refractive index \(=\frac{7}{5}\) ) of thickness \(1.4 \mathrm{~cm}\) is inserted between the lens and the screen. What is the distance of the object from the lens, so that its image is again focused on the screen?

282357 What is the refractive index of the material of a double convex lens having radii of curvature of \(5 \mathrm{~cm}\) and \(10 \mathrm{~cm}\) and focal length of \(\frac{20}{3} \mathrm{~cm}\)

282358 A point object is placed at a distance of \(60 \mathrm{~cm}\) from a convex lens of focal length \(30 \mathrm{~cm}\), if a plane of focal length \(30 \mathrm{~cm}\). If a plane mirror were put perpendicular to the principal axis of the lens and at distance of \(40 \mathrm{~cm}\) from it, the final image would be formed at a distance of

282355 A convex lens has power \(P\). It is cut into two halves along its principal axis. Further one piece (out of the two halves) is cut into two halves perpendicular to the principal axis (as shown in figures). Choose the incorrect options for the reported pieces.

282356 A convex lens focuses an object \(20 \mathrm{~cm}\) from it on a screen placed \(5 \mathrm{~cm}\) away from it. A glass plate (refractive index \(=\frac{7}{5}\) ) of thickness \(1.4 \mathrm{~cm}\) is inserted between the lens and the screen. What is the distance of the object from the lens, so that its image is again focused on the screen?

282357 What is the refractive index of the material of a double convex lens having radii of curvature of \(5 \mathrm{~cm}\) and \(10 \mathrm{~cm}\) and focal length of \(\frac{20}{3} \mathrm{~cm}\)

282358 A point object is placed at a distance of \(60 \mathrm{~cm}\) from a convex lens of focal length \(30 \mathrm{~cm}\), if a plane of focal length \(30 \mathrm{~cm}\). If a plane mirror were put perpendicular to the principal axis of the lens and at distance of \(40 \mathrm{~cm}\) from it, the final image would be formed at a distance of

282355 A convex lens has power \(P\). It is cut into two halves along its principal axis. Further one piece (out of the two halves) is cut into two halves perpendicular to the principal axis (as shown in figures). Choose the incorrect options for the reported pieces.

282356 A convex lens focuses an object \(20 \mathrm{~cm}\) from it on a screen placed \(5 \mathrm{~cm}\) away from it. A glass plate (refractive index \(=\frac{7}{5}\) ) of thickness \(1.4 \mathrm{~cm}\) is inserted between the lens and the screen. What is the distance of the object from the lens, so that its image is again focused on the screen?

282357 What is the refractive index of the material of a double convex lens having radii of curvature of \(5 \mathrm{~cm}\) and \(10 \mathrm{~cm}\) and focal length of \(\frac{20}{3} \mathrm{~cm}\)

282358 A point object is placed at a distance of \(60 \mathrm{~cm}\) from a convex lens of focal length \(30 \mathrm{~cm}\), if a plane of focal length \(30 \mathrm{~cm}\). If a plane mirror were put perpendicular to the principal axis of the lens and at distance of \(40 \mathrm{~cm}\) from it, the final image would be formed at a distance of

282355 A convex lens has power \(P\). It is cut into two halves along its principal axis. Further one piece (out of the two halves) is cut into two halves perpendicular to the principal axis (as shown in figures). Choose the incorrect options for the reported pieces.

282356 A convex lens focuses an object \(20 \mathrm{~cm}\) from it on a screen placed \(5 \mathrm{~cm}\) away from it. A glass plate (refractive index \(=\frac{7}{5}\) ) of thickness \(1.4 \mathrm{~cm}\) is inserted between the lens and the screen. What is the distance of the object from the lens, so that its image is again focused on the screen?

282357 What is the refractive index of the material of a double convex lens having radii of curvature of \(5 \mathrm{~cm}\) and \(10 \mathrm{~cm}\) and focal length of \(\frac{20}{3} \mathrm{~cm}\)

282358 A point object is placed at a distance of \(60 \mathrm{~cm}\) from a convex lens of focal length \(30 \mathrm{~cm}\), if a plane of focal length \(30 \mathrm{~cm}\). If a plane mirror were put perpendicular to the principal axis of the lens and at distance of \(40 \mathrm{~cm}\) from it, the final image would be formed at a distance of