Solve this following

Question: Prove that $f(x)=\left\{\begin{array}{l}2-x, \text { when } x2 \\ 2+x, \text { when } x \geq 2\end{array}\right.$ is discontinuous at $x=2$ Solution:...

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A wave pulse is travelling on a string with a speed v towards

Question: A wave pulse is travelling on a string with a speed $v$ towards the positive $x$-axis. The shape of the string at $t=0$ is given by $\mathrm{g}(\mathrm{x})=\mathrm{A} \sin (\mathrm{x} / \mathrm{a})$, where $\mathrm{A}$ and a are constants. (a) What are the dimensions of A and a? (b) Write the equation of the wave for a general time $t$, if the wave of the speed is $t$. Solution:...

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The displacement of the particle at x=0 of a stretched string carrying

Question: The displacement of the particle at $x=0$ of a stretched string carrying a wave in the positive $x$-direction is given by $\mathrm{f}(\mathrm{t})=\mathrm{A} \sin (\mathrm{t} / \mathrm{T})$ The wave speed is $v$. Write the wave equation. Solution:...

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Solve this following

Question: Prove that $f(x)=\left\{\begin{array}{c}\frac{1-\cos x}{x^{2}}, \text { when } x \neq 0 ; \\ 1, \text { when } x=0\end{array}\right.$ is discontinuous at $x=0$ Solution:...

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A pulse travelling on a string is represented by the function

Question: A pulse travelling on a string is represented by the function $y=\frac{a^{3}}{(x-v t)^{2}+a^{2}}$ Where $a=5 \mathrm{~mm}$ and $\mathrm{v}=20 \mathrm{~cm} / \mathrm{s}$. Sketch the shape of the string at $\mathrm{t}=0,1 \mathrm{~s}, 2 \mathrm{~s}$. Take $x=0$ in the middle of the string. Solution:...

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The Figure shows a wave pulse at t=0.

Question: The Figure shows a wave pulse at $t=0$. The pulse moves to the right with a speed at $10 \mathrm{~cm} / \mathrm{s}$. Sketch the shape of the string at $t=1 \mathrm{~s}, 2 \mathrm{~s}, 3 \mathrm{~s}$. Solution:...

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Solve this following

Question: Prove that $f(x)=\left\{\begin{array}{c}\frac{\sin 3 x}{x}, \text { when } x \neq 0 ; \\ 1, \text { when } x=0\end{array}\right.$ is discontinuous at $x=0$ Solution:...

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The equation of a wave travelling on a string stretched along

Question: The equation of a wave travelling on a string stretched along the $X$-axis is given by $\mathrm{Y}=\mathrm{A} . e^{-\left(\frac{x}{a}+\frac{t)^{2}}{T}\right.}$ (a) Write the dimensions of $A$, a and $T$. (b) Find the wave speed (c) In which direction is the wave travelling (d) Where is the maximum of the pulse located at $t=T$ ? At $t=2 T$ ? Solution: at $t=T ; x=-a$ $t=2 T ; x=-2 a$...

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A wave pulse passing on a string with a speed of 40 cm/s

Question: A wave pulse passing on a string with a speed of $40 \mathrm{~cm} / \mathrm{s}$ in the negative $x$-direction has its maximum at $x=0$ at $t=0$. Where will this maximum be located at $t=5 \mathrm{~s}$ ? Solution:...

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Prove that

Question: Prove that $f(x)=\left\{\begin{aligned} \frac{x^{2}-25}{x-5}, \text { when } x \neq 5 \\ 10, \text { when } x=5 \end{aligned}\right.$ is continuous at $x=5$ Solution:...

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Solve this following

Question: Prove that $f(x)=\left\{\begin{aligned} \frac{x^{2}-x-6}{x-3}, \text { when } x \neq 3 \\ 5, \text { when } x=3 \end{aligned}\right.$ is continuous at $x=3$ Solution:...

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Solve this following

Question: Show that $f(x)=\left(x^{2}+3 x+4\right)$ is continuous at $x=1$. Solution:...

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Solve this following

Question: Show that $f(x)=x^{2}$ is continues at $x=2$. Solution:...

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Water flows at a speed of 6 cm/s through a tube of radius 1cm.

Question: Water flows at a speed of $6 \mathrm{~cm} / \mathrm{s}$ through a tube of radius $1 \mathrm{~cm}$. Coefficient of viscosity of water at room temperature is $0.01$ poise. Calculating the Reynolds number. Is it a steady flow? Solution:...

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Estimate the speed of vertically falling raindrops from

Question: Estimate the speed of vertically falling raindrops from the following data. Radius of the drops $=0.02 \mathrm{~cm}$, viscosity of air $=$ $1.8 \times 10^{-4}$ poise, $g=9.9 \mathrm{~m} / \mathrm{s}^{2}$ and density of water $=1000 \mathrm{~kg} / \mathrm{m}^{3}$. Solution:...

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A metal sphere of radius 1 mm and mass 50 mg

Question: A metal sphere of radius $1 \mathrm{~mm}$ and mass $50 \mathrm{mg}$ falls vertically in glycerine. Find (a) the viscous force exerted by the glycerine on the sphere when the speed of the sphere is $1 \mathrm{~cm} / \mathrm{s}$, (b) the hydrostatic force exerted by the glycerine on the sphere and (c) the terminal velocity with which the sphere will moved down without acceleration. Density of glycerine = $1260 \mathrm{~kg} / \mathrm{m}^{3}$ and its coefficient viscosity at room temperatu...

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A wire forming a loop is dipped into soap solution and

Question: A wire forming a loop is dipped into soap solution and taken out so that a film of soap solution is formed. A loop of $6.28 \mathrm{~cm}$ long thread is gently put on the film and the film is pricked with a needle inside the loop. The thread loop takes the shape of a circle. Find the tension in the thread. Surface tension of soap solution $=0.030 \mathrm{~N} / \mathrm{m}$. Solution:...

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Solve this following

Question: If $A=\left(\begin{array}{cc}1 -1 \\ 2 -1\end{array}\right)$ and $B=\left(\begin{array}{cc}a 1 \\ b -1\end{array}\right)$ and $(A+B)^{2}=\left(A^{2}+B^{2}\right)$ then A. $a=2, b=-3$ B. $a=-2, b=3$ C. $a=1, b=4$ D. none of these Solution:...

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Consider an ice cube of edge

Question: Consider an ice cube of edge $1.0 \mathrm{~cm}$ kept in a gravity free hall. Find the surface area of the water when the ice melts. Neglect the difference in densities of ice and water. Solution:...

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Two larger glass plates are placed vertically and

Question: Two larger glass plates are placed vertically and parallel to each other inside a tank of water with separation between the plates equal to $1 \mathrm{~mm}$. find the rise of water in the space between the plates. Surface tension of water $=0.075 \mathrm{~N} / \mathrm{m}$. Solution:...

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Which one of the following is a scalar matrix?

Question: Which one of the following is a scalar matrix? A. $\left(\begin{array}{ll}1 1 \\ 1 1\end{array}\right)$ B. $\left(\begin{array}{ll}6 0 \\ 0 3\end{array}\right)$ c. $\left(\begin{array}{cc}-8 0 \\ 0 -8\end{array}\right)$ D. None of these Solution:...

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The lower end of a capillary tube of radius 1 mm is dipped vertically into mercury.

Question: The lower end of a capillary tube of radius $1 \mathrm{~mm}$ is dipped vertically into mercury. (a) Find the depression of mercury column in the capillary. (b) If the length dipped inside is half the answer of part (a), find the angle made by the mercury surface at the end of the capillary with the vertical. Surface tension of mercury $=0.465 \mathrm{~N} / \mathrm{m}$ and the contact angle of mercury with glass $=135^{\circ}$. Solution:...

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Solve this following

Question: If $\mathrm{A}$ is a 3-rowed square matrix and $|3 \mathrm{~A}|=\mathrm{k}|\mathrm{A}|$ then $\mathrm{k}=$ ? A. 3 B. 9 C. 27 D.1 Solution: Since the matrix is of order 3 so 3 will be taken common from each row or column. So, $k=27$ Tagging...

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A capillary tube of radius 1 mm is kept vertical with the lower end in water.

Question: A capillary tube of radius $1 \mathrm{~mm}$ is kept vertical with the lower end in water. (a) Find the height of water raised in the capillary. (b) If the length of the capillary tube is half the answer of part (a), find the angle $\theta$ made by the water surface in the capillary with the wall. Solution:...

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Solve this following

Question: If $A$ is a square matrix then $\left(A-A^{\prime}\right)$ is A. A null matrix B. An identity matrix C. A symmetric matrix D. A skew-symmetric matrix Solution:...

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