WBJEE Sample Questions

Ques- 1.

If a cyclist doubles his speed while negotiating a curve, how does the tendency to overturn vary?

a) Remains unchanged

b) Quadrupled

c) Doubled

d) Halved 

Ques- 2.

A body of mass m and radius r is released from rest along a smooth inclined plane of angle of inclinationθ . The angular momentum of the body about the instanta- neous point of contact after a time t from the instant of release is equal to:

a)(32 )mgrtsinθ

b)(23 )mgrtsinθ

c) Mgrt sinθ
d) Mgrt cosθ 

Ques- 3.

In the HCl molecule, the separation between the nuclei of the two atoms is about 1.27A◦ (1A◦ = 10 – 10m). The approximate location of the centre of mass of the molecule, assuming the chlorine atom to be about 35.5 times, massive as hydrogen is (from H atom): 
a) 1A◦

b) 25A◦
c) 1.5A◦

d) 1.24A◦ 

Ques- 4.

A body having moment of inertia about its axis of rota- tion equal to 3 kg – m2 is rotating with angular velocity equal to 3 rad/sec. Kinetic energy of this rotating body is the same as that of a body of mass 27 kg moving with a speed of:

a) 2.0 m/s

b) 1.0 m/s 

c) 0.5 m/s

d) 1.5 m/s 

Ques- 5.

The IUPAC name of the following compound is:

pastedGraphic.png

a) 2 –  nitro –  4 –  hydroxymethyl –  5 –  amino benzaldehyde

b) 3 –  amino –  4 –  hydroxymethyl –  5 –  nitrobenzaldehyde

c) 4 –  amino –  2 –  formyl –  5 –  hydroxymethyl nitrobenzene

d) 5 –  amino –  4 –  hydroxymethyl –  2 –  nitrobenzaldehyde

Ques- 6.

Which carbocation is most stabilised among following?

a) pastedGraphic.png

b) pastedGraphic_1.png

c) pastedGraphic_2.png

d) pastedGraphic_3.png

Ques- 7.

Arrange the following in increasing order of heat of hydrogenation:

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a) P > Q > R > S

b) Q > P > S > R

c) R > S > Q > P

d) Q > S > R > P

Ques- 8.

Let the tangents to the curve x2 + 2x –4y + 9 = 0 at the point P(1, 3) on it meet the y-axis at A. Let the line

passing through P and parallel to the line x – 3y = 6 meet the parabola y2 = 4x at B. If B lies on the line 2x –

3y = 8, then (AB)2

is equal to ______

Ques- 9.

Let the image of the point P (1, 2, 3) in the plane 2x – y + z = 9 be Q. If the coordinates of the point R are (6,

10, 7). then the square of the area of the triangle PQR is ____.

Ques- 10.

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : Earth has atmosphere whereas moon doesn’t have any atmosphere.

Reason R : The escape velocity on moon is very small as compared to that on earth.

In the light of the above statements. choose the correct answer from the options given below:

(1) Both A and R are correct and R is the correct explanation of A

(2) A is false but R is true

(3) Both A and R are correct but R is NOT the correct explanation of A

(4) A is true but R is false