JEE 2020: Weekly Quiz 25 (07.09.2019) for JEE & BITSAT Exams

Question 1

Putrescine

present in almost all mammalian cells, where they are believed to be involved in cell differentiation and proliferation. This can be prepared by

Question 2

Consider the two columns below :

Column ‘A’

A) Hofmann rearrangement

B) Curtius rearrangement

C) Lossen rearrangement

Column ‘B’

1) Isocyanate

2) Br₂ + NaOH

3)

Which of the following match is correct :

Question 3

Which is maximum basic in nature?

Question 4

Identify the product P in the following reaction.

Question 5

Question 6

The major product obtained in the photobromination of 2-methyl butane is

Question 7

The product of the reaction between ethyl benzene and N-bromosuccinamide is

Question 8

Which of the following statements is wrong?

Question 9

In the given reaction,

the product ‘A’ is

Question 10

In the reactions given below

R–Cl product A

R–Cl product B

the compounds A and B are

Question 11

The magnetic flux across a lop of resistance 10 Ω is given by ϕ = 5t² – 4t + 1 weber. How much current is induced in the loop after 0.2 sec ?

Question 12

A closed Gaussian surface of a radius r, which is placed in a magnetic field

then find the amount of magnetic flux flowing through the surface,

Question 13

A coil of area 5cm² having 20 turns is placed in a uniform magnetic field of 10³ gauss. The normal to the plane of coil makes an angle. 30 ° with the magnetic field. The flux through the coil is

Question 14

In the arrangement shown in given figure current from A to B is increasing in magnitude. Induced current in the loop will

Question 15

An electric current i₁ can flow either direction through loop (1) and induced current i₂ in loop (2). Positive i₁ is when current is from ‘a’ to ‘b’ in loop (1) and positive i₂ is when the current is from ‘c’ to ‘d’ in loop (2)

In an experiment, the graph of i₂ against time ‘t’ is as shown below

Which one(s) of the following graphs could have caused i₂ to behave as given above.

Question 16

The magnetic field shown in the figure increases at a constant rate of 30 mT/sec. If the circular loop has the radius of 5 cm and resistance 45 Ω. Find the current in the wire if the switch S is closed.

Question 17

An inductor of inductance 8 H and zero resistance is connected with battery and fuse as shown in the figure. Fuse has the zero resistance and will blow when the current through it reaches 4 A. The switch is closed at t = 0. The fuse will blow

Question 18

In two single turn circular loop of wire have radii 20 cm and 2 cm. The loops lies in the same plane and are concentric. Find the mutual inductance of the pair is

Question 19

A circular ring is fixed in a gravity free space and one point of the ring is earthed. Now a magnet is placed along axis of the ring at a distance from its centre such that the nearer pole is North Pole as shown in figure. A sharp impulse is applied on the magnet so that it starts to move toward the ring. Then,

Question 20

A closed circuit consists of a resistance R, induction L and a source of emf E are connected in series. If the induction of a coil is abruptly decreases to L/4(by removing its magnetic core), the new current immediately after this moment is (Comment: before decreasing the inductance the circuit is in steady state)