# An Object is Placed at a Distance of 40cm from a Biconvex Lens of Focal Length 20cm forms

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You may be looking for the answer to a bit harder question that says ‘An Object is Placed at a Distance of 40cm from a Biconvex Lens of Focal Length 20cm forms’. Well, this is the question that usually can be found in some online quizzes and also in the Physic or Science test.

If you need the answer for this question, no worries, we’ll show you the correct answer in our post below! Let’s take a look for the answer!

We got the answer for the questions of ‘An Object is Placed at a Distance of 40cm from a Biconvex Lens of Focal Length 20cm forms’ from some sources. As the question is commonly found in some online quizzes, so we get the answer easily.

• Question: An Object is Placed at a Distance of 40cm from a Biconvex Lens of Focal Length 20cm forms?

a. real, inverted and enlarged

b. virtual, upright and of the same size as object

c. real, inverted and diminished

d. real, inverted and of the same size as object

• Correct Answer: d. real, inverted and of the same size as object

Some Similar Questions at BYJU Site

We’ll also show you a number of similar questions that we get from BYJU’s site that you can access HERE. Here are some questions that are the similar to the questions above:

• Question 1:

When an object is placed 10 cm in front of lens A, the image is real, inverted, magnified and formed at a great distance. When the same object is placed 10 cm in front of lens B, the image formed is real, inverted and the same size as the object.

a. What is the focal length of lens A?

b. What is the focal length of lens B?

c. What is the nature of lens A?

d. What is the nature of lens B?

a. The focal length of lens A is 10 cm as only a converging lens forms a real, inverted, magnified image at great distance when the object is placed at the focus of the lens.

b. The focal length of lens B is 5 cm as only a converging lens forms a real, inverted and same size image of the object when the object is placed at 2F position of the lens.

c. Lens A is a converging (convex) lens as only a converging lens forms a real image.

d. Lens B is a converging (convex) lens as only a converging lens forms a real image.

• Question 2:

An object is kept at a distance of 30 cm from the centre of a convex lens along its principal axis whose focal length is 15 cm. What can be concluded about the image formed?

a. Virtual, Inverted and same size

b. Virtual, Inverted and enlarged

c. Real, Inverted and same size

d. Real, Inverted and enlarged

Answer: c. Real, Inverted and same size

• Question 3:

Where must the object be placed for the image formed by a converging lens to be:

a. real, inverted and smaller than the object?

b. real, inverted and same size as the object?

c. real, inverted and larger than the object?

d. virtual, upright and larger than the object?

For a convex lens:

a. To form a real, inverted and smaller image than the object, the object should be beyond 2F .

b. To form a real and inverted image, which is the same size as that of the object, the object should be at 2F.

c. To form a real, inverted and larger image than the object, the object should be between F and 2F.

d. To form a virtual, upright and larger image than the object, the object should be between F(focus) and the optical centre.

• Question 4:

When an object is within the focal length of a convex lens, the image formed is….

a. real and inverted.

b. virtual and magnified.

c. virtual and the same size.

d. real and magnified.

• Question 5:

Complete the following sentences!

a. An object is placed at a distance of more than 40 cm from a convex lens of focal length 20 cm. The image formed is real, inverted and ……….

b. An object is placed at a distance 2f from a convex lens of focal length f. The size of the image formed is ………… that of the object.

c. An object is placed at a distance 5 cm from a convex of focal length 10 cm. The image formed is virtual, upright and …………

a. diminished

b. equal

c. magnified

Some Exercise Questions at BYJU Site

We also show you a number of exercise questions that may be useful for you when taking some online quizzes. Here are they:

1. An electric heater of resistance 8 Ω takes a current of 15 A from the mains supply line. Calculate the rate at which heat is developed in the heater.

Answer: I = 15 A, R = 8 Ω

Rate of heat produced = Power = I2R = (15)2(8) = 1800 J/s

2. What is the mass of a proton ?

Answer: Mass of a proton is 1.672×1027kg (1.00728 amu)

3. The unit of electric dipole moment is:

a. newton

c. debye

d. coulomb

4. The efficiency of the heat engine is

a. 75%

b. 33%

c. 50%

d. 25%

e. 100%

5. In the RC circuit shown, the switch is closed at t=0. Graphs showing variation of a potential (VR) across resistance and potential (VC) across capacitors are given. Then the constant of the circuit is approximately equal to…

a. 100 ms

b. 145 ms

c. 200 ms

d. 300 ms