WB JEE 2018 | Properties of Matter Question 18 | Physics

WB JEE 2018

MCQ (Single Correct Answer)

-0.25

What will be the approximate terminal velocity of a rain drop of diameter $${1.8 \times {{10}^{ - 3}}}$$ m, when density of rain water $$ \approx $$ $${1.8 \times {{10}^{ - 5}}}$$ N-sm^$$-$$2 (Neglect buoyancy of air)

49 ms^$$-$$1

98ms^$$-$$1

392 ms^$$-$$1

980 ms^$$-$$1

WB JEE 2017

MCQ (Single Correct Answer)

-0.25

A uniform capillary tube of length l and inner radius r with its upper end sealed is submerged vertically into water. The outside pressure is p₀ and surface tension of water is $$\gamma$$. When a length x of the capillary is submerged into water, it is found that water levels inside and outside the capillary coincide. The value of x is

$${l \over {\left( {1 + {{{p_0}r} \over {4\gamma }}} \right)}}$$

$$\left( {1 - {{{p_0}r} \over {4\gamma }}} \right)$$

$$\left( {1 - {{{p_0}r} \over {2\gamma }}} \right)$$

$${l \over {\left( {1 + {{{p_0}r} \over {2\gamma }}} \right)}}$$

WB JEE 2017

MCQ (Single Correct Answer)

-0.25

A liquid of bulk modulus k is compressed by applying an external pressure such that its density increases by 0.01%. The pressure applied on the liquid is

$${k \over {10000}}$$

$${k \over {1000}}$$

1000 k

0.01 k

WB JEE 2017

MCQ (Single Correct Answer)

-0.25

A solid rectangular sheet has two different coefficients of linear expansion $$\alpha$$₁ and $$\alpha$$₂ along its length and breadth respectively. The coefficient of surface expansion is (for $$\alpha$$₁ t << 1, $$\alpha$$₂t < <1)

$${{{\alpha _1} + {\alpha _2}} \over 2}$$

$$2({\alpha _1} + {\alpha _2})$$

$${{4{\alpha _1}{\alpha _2}} \over {{\alpha _1} + {\alpha _2}}}$$

$${\alpha _1} + {\alpha _2}$$