Recent questions tagged jeemain

Three particles, each of mass m are placed at the vertices of a right angled triangle as shown in figure. The position vector of the centre of mass of the system is ( O is the origin and $ \overrightarrow i , \overrightarrow j, \overrightarrow k $ are unit vectors )

asked Oct 9, 2013 by thanvigandhi_1

1 answer

A balloon starting from rest ascends vertically with uniform acceleration to a height of 100 m in 10 sec. The force on the bottom of the balloon by a mass of 50 kg is $( g=10\: ms^{-2})$

asked Oct 9, 2013 by thanvigandhi_1

1 answer

Find the value of $\tan 22\large\frac{1}{2}^{\large\circ}$

asked Oct 9, 2013 by sreemathi.v

1 answer

A body of mass 300 kg is moved through 10 m along a smooth inclined plane of angle $30^{\circ}$. The work done in moving in joules is $(g= 9.8\: ms^{-2})$

asked Oct 9, 2013 by thanvigandhi_1

1 answer

A body is thrown vertically upward from a point 'A' 125 m above the ground. It goes up to a maximum height of 250 m above the ground and passes through 'A' on its downward journey. The velocity of the body when it is at a height of 70 m above the ground is$ ( g = 10 \: ms^{-2})$

asked Oct 9, 2013 by thanvigandhi_1

1 answer

A minute hand of a clock is 20cm long.How far does the tip of the hand move in 20 minutes.

asked Oct 9, 2013 by sreemathi.v

1 answer

A person reaches a point directly opposite on the other bank of a river. The velocity of the water in the river is 4 $ms^{-1}$ and the velocity of the person in still water is 5 $ms^{-1}$. If the width of the river is 84.6 m , time taken to cross the river in seconds is

asked Oct 9, 2013 by thanvigandhi_1

1 answer

In the equation $ \bigg( \large\frac{1}{P \beta} \bigg)= \large\frac{y}{k_BT}$, where P is the pressure, y is the distance, $k_B$ is Boltzmann constant and T is the temperature. Dimensions of $ \beta $ are

asked Oct 9, 2013 by thanvigandhi_1

1 answer

If $X$ is a binomial variate with the range $\{0,1,2,3,4,5,6\}$ and $P(X=2)=4P(X=4),$ then the parameter p of X is :

asked Oct 9, 2013 by meena.p

1 answer

If $m$ and $\sigma^2$ are the mean and variance of the random variable X, whose distribution is given by: X=x: 0 1 2 3 P(X=x): 1/3 1/2 0 1/6 then:

asked Oct 9, 2013 by meena.p

1 answer

Suppose that $E_1$ and $E_2$ are two events of a random experiment such that $P(E_1)=\large\frac{1}{4},$$ P(E_2/E_1)=\large\frac{1}{4},$ Observe the lists given below:

asked Oct 9, 2013 by meena.p

1 answer

Find $\cos 55^{\large\circ}+\cos 65^{\large \circ}+\cos 175^{\large\circ}$

asked Oct 9, 2013 by sreemathi.v

2 answers

Copper and carbon wires are connected in series and the combined resister is kept at $0^{\circ} C$. Assuming the combined resistance does not vary with temperature, the ratio of the resistances of carbon and copper wires at $0^{\circ}C$ is ( Temperature coefficients of resistivity of copper and carbon respectively are $4 \times 10^{-3} / ^{\circ}C\: and \: -0.5 \times 10^{-3}/^{\circ}C$)

asked Oct 9, 2013 by thanvigandhi_1

1 answer

The probability of choosing randomly a number c from the set {1,2,3,......,9} such that the quadratic equation $x^2+4x+c=0$ has real roots is :

asked Oct 9, 2013 by meena.p

1 answer

The expression $\tan^2\alpha+\cot^2\alpha$ is

asked Oct 9, 2013 by sreemathi.v

1 answer

A parallel plate capacitor with a dielectric slab with a dielectric constant 3 filling the space betwen the plates is charged to a potential V. The battery is then disconnected and the dielectric slab is withdrawn. It is then replaced with another dielectric slab of dielectric constant 2. If the energies stored in the capacitor before and after the dielectric slab is changed are $E_1\: and E_2$, then $E_1 / E_2$ are

asked Oct 9, 2013 by thanvigandhi_1

1 answer

If $A$ and $B$ are events of a random experiment such that $P(A \cup B)=\large\frac{4}{5},$$ P(\bar {A} \cup \bar {B})=\large\frac{7}{10}$ and $P(B)=\large\frac{2}{5},$ then $P(A)=$

asked Oct 9, 2013 by meena.p

1 answer

The volume of the tetrahedron having the edges $\overrightarrow {i}+2 \overrightarrow {j}-\overrightarrow {k},\overrightarrow {i}+\overrightarrow {j}+ \overrightarrow {k},\overrightarrow {i}+\overrightarrow {j}+ \lambda \overrightarrow {k}$ as coterminous, is $\large\frac{2}{3} $ cubic units. Then $\lambda=$

asked Oct 9, 2013 by meena.p

1 answer

Find the value of $\sin(105^{\large\circ})$

asked Oct 9, 2013 by sreemathi.v

1 answer

Two capacitors having capacitances $C_1\: and \: C_2$ are charged with 120 V and 200 V batteries respectively. When they are connected in parallel now, it is found that the potential on each one of them is zero. Then

asked Oct 9, 2013 by thanvigandhi_1

1 answer

Suppose $\overrightarrow {a}= \lambda \overrightarrow {i}- 7 \overrightarrow {j}+3 \overrightarrow {k}, \overrightarrow {b}= \lambda \overrightarrow {i}+\overrightarrow {j}+2 \lambda \overrightarrow {k}$. If the angle between $\overrightarrow {a}$ and $\overrightarrow {b}$ is greater than $90^{\circ},$ then $\lambda$ satisfies the inequality:

asked Oct 9, 2013 by meena.p

1 answer

If $m_1,m_2,m_3$ and $m_4$ are respectively the magnitudes of the vectors $\overrightarrow{a_1}=2 \overrightarrow{i}-\overrightarrow{j}+\overrightarrow{k},\;\;\overrightarrow{a_2}=3 \overrightarrow{i}-4\overrightarrow{j}-4\overrightarrow{k},\;\;\overrightarrow{a_3}=\overrightarrow{i}+\overrightarrow{j}-\overrightarrow{k}$ and $\overrightarrow{a_4}=-\overrightarrow{i}+3 \overrightarrow{j}+\overrightarrow{k}$ then the correct order of $m_1,m_2,m_3,m_4$ is :

asked Oct 9, 2013 by meena.p

1 answer

The value of $\tan\bigg[\cos^{-1}\big(\large\frac{4}{5}\big)$$+\tan^{-1}\big(\large\frac{2}{3}\big)\bigg]$ is

asked Oct 9, 2013 by sreemathi.v

1 answer

If $\overrightarrow {a}=-\overrightarrow {i}+\overrightarrow {j}+2\overrightarrow {k} , \overrightarrow {b}=2\overrightarrow {i}-\overrightarrow {j}-\overrightarrow {k}$ and $\overrightarrow {c}=-2 \overrightarrow {i}+\overrightarrow {j}+3 \overrightarrow {k},$ then the angle between $2 \overrightarrow {a}-\overrightarrow {c}$ and $\overrightarrow {a}+\overrightarrow {b}$ is :

asked Oct 9, 2013 by meena.p

1 answer

The angle between the lines whose direction cosines satisfy the equations $l+m+n=0,l^2+m^2-n^2=0$ is :

asked Oct 9, 2013 by meena.p

1 answer

If $f(\theta)=(\sin\theta+cosec\theta)^2+(\cos\theta+\sec\theta)^2$ then minimum value of $f(\theta)$ is

asked Oct 9, 2013 by sreemathi.v

1 answer

In a quadrilateral $ABCD,$ the point P divides DC in the ratio $1:2$ and Q is the mid point of AC.If $\overrightarrow {AB}+2 \overrightarrow {AD}+\overrightarrow {BC}-2 \overrightarrow {DC}=k \overrightarrow {PQ}$, then $k= $

asked Oct 9, 2013 by meena.p

1 answer

In a $\Delta ABC$ the value of the expression $cosec A(\sin B\cos C+\cos B\sin C)$ is

asked Oct 9, 2013 by sreemathi.v

1 answer

The value of expression $\large\frac{1-4\sin 10^{\large\circ}\sin 70^{\large\circ}}{2\sin 10^{\large\circ}}$

asked Oct 9, 2013 by sreemathi.v

1 answer

$P$ is a point on the segment joining the feet of two vertical poles of heights $a$ and $b$. The angles of elevation of the tops of the poles from P are $45^{\circ}$ each. Then the square of the distance between the tops of the poles is :

asked Oct 9, 2013 by meena.p

1 answer

In a $\Delta ABC \; \large\frac{(a+b+c)(b+c-a)(c+a-b)(a+b-c)}{4b^2c^2}$$=$

asked Oct 9, 2013 by meena.p

1 answer

The value of the expression $(\sqrt 3\sin 75^{\large\circ}-\cos 75^{\large\circ})$ is

asked Oct 9, 2013 by sreemathi.v

1 answer

In any $\Delta ABC,a(b \cos C-c \cos B)=$

asked Oct 9, 2013 by meena.p

0 answers

$ \sin h^{-1} 2+ \sin h^{-1}3=x => \cos h\; x=$

asked Oct 9, 2013 by meena.p

1 answer

$\cos ^{-1}\bigg(\large\frac{-1}{2}\bigg)$$-2 \sin ^{-1} \bigg(\large\frac{1}{2}\bigg)$$+3 \cos ^{-1} \bigg(\large\frac{-1}{\sqrt 2}\bigg)$$-4 \tan ^{-1}(-1)=$

asked Oct 9, 2013 by meena.p

1 answer

If $\alpha\cos^23\theta+\beta\cos^4\theta=16\cos^6\theta+9\cos^2\theta$ is an identity then

asked Oct 9, 2013 by sreemathi.v

1 answer

If $3 \cos x \neq 2 \sin x,$ then the general solution of $\sin ^2 x -\cos 2x=2 -\sin 2x$ is $x=$

asked Oct 9, 2013 by meena.p

1 answer

$\cos A \cos 2A \cos 4A....... \cos 2^{n-1} A=$

asked Oct 9, 2013 by meena.p

1 answer

$\large\frac{\cos x}{\cos (x-2y)}$$=\lambda => \tan (x-y) \tan y=$

asked Oct 9, 2013 by meena.p

1 answer

If $\tan\alpha=\large\frac{x}{x+1}$ and $\tan \beta=\large\frac{1}{2x+1}$ then $\alpha+\beta$ is

asked Oct 9, 2013 by sreemathi.v

1 answer

The period of $\sin ^4 x+\cos ^4x $ is :

asked Oct 9, 2013 by meena.p

1 answer

If $n$ is an integer which leaves remainder one when divided by three, then $(1+\sqrt {3}i)^n+(1-\sqrt {3}i)^n=$

asked Oct 9, 2013 by meena.p

1 answer

If $\tan x=\large\frac{b}{a}$ then the value of $a\cos 2x+b\sin 2x$ is

asked Oct 9, 2013 by sreemathi.v

1 answer

The locus of z satisfying the inequity $\bigg|\large\frac{z+2i}{2z+i}\bigg| < 1,$ where $z=x+iy,$ is :

asked Oct 9, 2013 by meena.p

1 answer

If $\alpha$ and $\beta$ are the roots of $x^2-2x+4=0,$ then the value of $\alpha ^6+\beta ^6$ is :

asked Oct 9, 2013 by meena.p

1 answer

If $\begin{bmatrix} 1 & -1 & x \\ 1 & x & 1 \\ x & -1 &1 \end {bmatrix}$ has no inverse, then the real value of x is :

asked Oct 9, 2013 by meena.p

1 answer

The value of $\tan 81^{\large \circ}-\tan 63^{\large\circ}-\tan 27^{\large\circ}+\tan 9^{\large \circ}$ is

asked Oct 9, 2013 by sreemathi.v

1 answer

If $x,y,z$ are all positive and are the $p$th, $q$th and $r$th terms of a geometric progression respectively, then the value of the determinant $\begin{vmatrix} \log x & p & 1 \\ \log z & r &1 \\ \log z & r & 1 \end{vmatrix}=$

asked Oct 9, 2013 by meena.p

1 answer

If $cosec A+\cot A=\large\frac{11}{2}$ then $\tan A$ is

asked Oct 9, 2013 by sreemathi.v

1 answer

If one of the roots of $\begin {vmatrix} 3 & 5 & x \\ 7 & x & 7 \\ x & 5 & 3 \end {vmatrix}=0$ is $-10,$ then the other roots are :

asked Oct 9, 2013 by meena.p

1 answer

Ask Questions, Get Answers