Archives

Let a plane P contain two lines….

Let a plane P contain two lines = (-1, 1 ,1)Equation of plane-1(x -1)+1(y-0) +1(z-0) = 0⇒x-y-z-1 = 0Foot of the perpendicular from m... View Article

For a positive integer n, (1+1/x)ⁿ is expanded in increasing powers of x. If three consecutive coefficients in this expansion are in the ratio, 2:5:12, then n is equal to

Solution: Let 3 consecutive coefficients are nCr-1 : nCr : nCr+1::2:5:12 nCr-1/ nCr = 2/5 and nCr/ nCr+1 = 5/12 r/(n-r+1) = 2/5 and... View Article

If the variance of the terms in an increasing A.P., b₁, b₂, b₃, …., b₁₁ is 90, then the common difference of this A.P. is

Solution: Var(x) = (Ʃbi2/11)- (Ʃbi/11)2 90 = [(11a2+385d2+110ad)/11]-[(11a+55d)/11]2 90 = a2+35d2+10ad- (a+5d)2 90 = a2+35d2+10ad-... View Article

Find the value of (dy/dx) at x = 0

Question: If y = , then (dy/dx) at x = 0 is: Solution: y = where tanθ = 4/3 cos-1[cos(kx+a)] = kx+a as kx+a∈[0, π] y = cos-1(cos... View Article

1 ns is defined as

1) 10-9 s of Kr–clock of 1650763.73 oscillations 2) 10-9 s of Kr–clock of 6521389.63 oscillations 3) 10-9 s of Cs–clock of... View Article

Two full turns of the circular scale of a screw gauge cover a distance of 1 mm on its main scale.

Two full turns of the circular scale of a screw gauge cover a distance of 1 mm on its main scale. The total number of divisions of 1 mm on its... View Article

A body of mass m = 3.513 kg is moving along the x-axis with a speed of 5.00 ms^-1. The magnitude of its momentum is recorded as

1) 17.6 kg ms-1 2) 17.565 kg ms-1 3) 17.56 kg ms-1 4) 17.57 kg ms-1 Answer: 1) 17.6 kg ms-1 Solution: Momentum, p=m×v... View Article

A student has measured the length of a wire equal to 0.04580 m. This value of length has the number of significant figures equal to

1) five 2) four 3) six 4) None of these Answer:2) four Solution: Zero on right having decimal place are counted. For a number less than 1,... View Article

If 3.8×10^-6 is added to 4.2×10^-5 giving due regard to significant figures, then the result will be

1) 4.58×10-5 2) 4.6×10-5 3) 4.5×10-5 4) None of these Answer: 2) 4.6×10-5 Solution: Adding 3.8... View Article

In an experiment the angles are required to be measured using an instrument.

In an experiment the angles are required to be measured using an instrument. 29 division of the main scale exactly coincide with the 30 division... View Article

The respective number of significant figures for the numbers 23.023 , 0.0003 and 2.1×10^-3 are

1) 5, 1, 2 2) 5, 1, 5 3) 5, 5, 2 4) 4, 4, 2 Answer: 1) 5, 1, 2 Solution: Number of significant figures in 23.023 is 5. The number... View Article

A screw gauge gives the following reading when used to measure the diameter of a wire.

Main scale reading : 0 mm Circular scale reading : 52 divisions Given that, 1 mm on main scale corresponds to 100 divisions of the circular... View Article

The square root of the product of inductance and capacitance has the dimension of

1) length 2) mass 3) time 4) No dimension Answer: 3) time Solution: The square root of the product of inductance and... View Article

The modulus of elasticity is dimensionally equivalent to

1) strain 2) force 3) stress 4) coefficient of viscosity Answer: 3) stress Solution: Elastic Modulus = Stress/StainStress is the force... View Article

A spectrometer gives the following reading when used to measure the angle of a prism.

A spectrometer gives the following reading when used to measure the angle of a prism. Main scale reading 58.5 degree. Vernier scale reading 9... View Article

The diameter of a cylinder is measured using a vernier callipers with no zero error.

The diameter of a cylinder is measured using a vernier callipers with no zero error. It is found that the zero of the vernier scale lies between... View Article

Out of the following pairs, which one does not have identical dimensions?

1) Angular momentum and Planck's constant 2) Impulse and momentum 3) Moment of inertia and moment of a force 4) Work and torque Answer: 3)... View Article

Dimensions of impulse are same as that of

1) force 2) momentum 3) energy 4) acceleration Answer: 2) momentum Solution: Impulse = Force × Time. Dimensional formula of... View Article

The only mechanical quantity which has negative dimension of mass is

1) angular momentum 2) torque 3) coefficient of thermal conductivity 4) gravitational constant Answer: 4) gravitational constant... View Article

lim_x→0 x² sin (π / x) =

1) 1 2) 0 3) does not exist 4) ∞ Solution: (2) 0... View Article

M	T	W	T	F	S	S
			1	2	3	4
5	6	7	8	9	10	11
12	13	14	15	16	17	18
19	20	21	22	23	24	25
26	27	28	29	30	31