QBManager

TEST SERIES (PHYSICS FST)

266419 The primary winding of tranformer has 500 turns whereas its secondary has 5000 turns. The primary is connected to an AC supply of $20 V - 50 Hz$ . The secondary will have an output of :

1

2 V, 5 Hz

2

200 V, 500 Hz

3

2 V, 50 Hz

4

200 V, 50 Hz

Explanation:

d
$\begin{aligned} \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ V_{s} = \frac{N_{S}}{N_{F}} V_{P} = \frac{5000}{500} \times 20 = 200 V \end{aligned}$

**NCERT-XII-I-194**

TEST SERIES (PHYSICS FST)

266420 A body of mass $m$ is suspended from a string of length I. What is minimum horizontal velocity that should be given to the body in its lowest position so that it may complete one full revolution in the vertical plane with the point of suspension as the centre of the circle

1

v = \sqrt{2 \lg}

2

v = \sqrt{319}

3

v = \sqrt{4 ∣ g}

4

v = \sqrt{5 \lg}

**NCERT-XI-I-63**

TEST SERIES (PHYSICS FST)

266421 On increasing the temperature of a conductor, its resistance increase because

1 Relaxation time decreases

2 Mass of the electrons increases

3 Electron density decreases

4 None of these

Explanation:

a
On increasing the temperature thermal speed of free electrons increase hence relaxation time decreases, and so resistance increases.
$as R = (\frac{m}{π r^{2} τ}) \frac{ℓ}{A}$

**NCERT-XII-I-90**

TEST SERIES (PHYSICS FST)

266422 A thin equiconvex lens has focal length 10 cm and refractive index 1.5. One of its faces is now silvered and for an objet placed at a distance $u$ in from of it, the image coincides with the object. The value of $u$ is

1 10 cm

2 5 cm

3 20 cm

4 15 cm

Explanation:

b
$\begin{aligned} \frac{1}{f} = \frac{μ - 1}{2 R} \\ \frac{1}{10} = \frac{0.5}{2 R} \\ R = 10 cm \end{aligned}$

$\begin{aligned} \frac{1}{f_{e q}} = \frac{- 2}{f_{L}} + \frac{1}{f_{m}} = - \frac{2}{10} + \frac{1}{+ 5} \\ f_{r} = 2.5 cm \\ u = 2 f_{r} = - 5 cm \end{aligned}$

**NCERT-XII-II-232**

TEST SERIES (PHYSICS FST)

266423 A bomb of mass 3 m kg explodes into two pieces of mass m kg and 2 m kg . If the velocity of m kg mass is $16 m / s$ , the total kinetic energy released in the explosion is

1 192 m ل

2 96 m J

3 384 m d

4 768 m ل

**NCERT-XI-I-83**

TEST SERIES (PHYSICS FST)

266419 The primary winding of tranformer has 500 turns whereas its secondary has 5000 turns. The primary is connected to an AC supply of $20 V - 50 Hz$ . The secondary will have an output of :

1

2 V, 5 Hz

2

200 V, 500 Hz

3

2 V, 50 Hz

4

200 V, 50 Hz

Explanation:

d
$\begin{aligned} \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ V_{s} = \frac{N_{S}}{N_{F}} V_{P} = \frac{5000}{500} \times 20 = 200 V \end{aligned}$

**NCERT-XII-I-194**

TEST SERIES (PHYSICS FST)

266420 A body of mass $m$ is suspended from a string of length I. What is minimum horizontal velocity that should be given to the body in its lowest position so that it may complete one full revolution in the vertical plane with the point of suspension as the centre of the circle

1

v = \sqrt{2 \lg}

2

v = \sqrt{319}

3

v = \sqrt{4 ∣ g}

4

v = \sqrt{5 \lg}

**NCERT-XI-I-63**

TEST SERIES (PHYSICS FST)

266421 On increasing the temperature of a conductor, its resistance increase because

1 Relaxation time decreases

2 Mass of the electrons increases

3 Electron density decreases

4 None of these

Explanation:

a
On increasing the temperature thermal speed of free electrons increase hence relaxation time decreases, and so resistance increases.
$as R = (\frac{m}{π r^{2} τ}) \frac{ℓ}{A}$

**NCERT-XII-I-90**

TEST SERIES (PHYSICS FST)

266422 A thin equiconvex lens has focal length 10 cm and refractive index 1.5. One of its faces is now silvered and for an objet placed at a distance $u$ in from of it, the image coincides with the object. The value of $u$ is

1 10 cm

2 5 cm

3 20 cm

4 15 cm

Explanation:

b
$\begin{aligned} \frac{1}{f} = \frac{μ - 1}{2 R} \\ \frac{1}{10} = \frac{0.5}{2 R} \\ R = 10 cm \end{aligned}$

$\begin{aligned} \frac{1}{f_{e q}} = \frac{- 2}{f_{L}} + \frac{1}{f_{m}} = - \frac{2}{10} + \frac{1}{+ 5} \\ f_{r} = 2.5 cm \\ u = 2 f_{r} = - 5 cm \end{aligned}$

**NCERT-XII-II-232**

TEST SERIES (PHYSICS FST)

266423 A bomb of mass 3 m kg explodes into two pieces of mass m kg and 2 m kg . If the velocity of m kg mass is $16 m / s$ , the total kinetic energy released in the explosion is

1 192 m ل

2 96 m J

3 384 m d

4 768 m ل

**NCERT-XI-I-83**

TEST SERIES (PHYSICS FST)

266419 The primary winding of tranformer has 500 turns whereas its secondary has 5000 turns. The primary is connected to an AC supply of $20 V - 50 Hz$ . The secondary will have an output of :

1

2 V, 5 Hz

2

200 V, 500 Hz

3

2 V, 50 Hz

4

200 V, 50 Hz

Explanation:

d
$\begin{aligned} \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ V_{s} = \frac{N_{S}}{N_{F}} V_{P} = \frac{5000}{500} \times 20 = 200 V \end{aligned}$

**NCERT-XII-I-194**

TEST SERIES (PHYSICS FST)

266420 A body of mass $m$ is suspended from a string of length I. What is minimum horizontal velocity that should be given to the body in its lowest position so that it may complete one full revolution in the vertical plane with the point of suspension as the centre of the circle

1

v = \sqrt{2 \lg}

2

v = \sqrt{319}

3

v = \sqrt{4 ∣ g}

4

v = \sqrt{5 \lg}

**NCERT-XI-I-63**

TEST SERIES (PHYSICS FST)

266421 On increasing the temperature of a conductor, its resistance increase because

1 Relaxation time decreases

2 Mass of the electrons increases

3 Electron density decreases

4 None of these

Explanation:

a
On increasing the temperature thermal speed of free electrons increase hence relaxation time decreases, and so resistance increases.
$as R = (\frac{m}{π r^{2} τ}) \frac{ℓ}{A}$

**NCERT-XII-I-90**

TEST SERIES (PHYSICS FST)

266422 A thin equiconvex lens has focal length 10 cm and refractive index 1.5. One of its faces is now silvered and for an objet placed at a distance $u$ in from of it, the image coincides with the object. The value of $u$ is

1 10 cm

2 5 cm

3 20 cm

4 15 cm

Explanation:

b
$\begin{aligned} \frac{1}{f} = \frac{μ - 1}{2 R} \\ \frac{1}{10} = \frac{0.5}{2 R} \\ R = 10 cm \end{aligned}$

$\begin{aligned} \frac{1}{f_{e q}} = \frac{- 2}{f_{L}} + \frac{1}{f_{m}} = - \frac{2}{10} + \frac{1}{+ 5} \\ f_{r} = 2.5 cm \\ u = 2 f_{r} = - 5 cm \end{aligned}$

**NCERT-XII-II-232**

TEST SERIES (PHYSICS FST)

266423 A bomb of mass 3 m kg explodes into two pieces of mass m kg and 2 m kg . If the velocity of m kg mass is $16 m / s$ , the total kinetic energy released in the explosion is

1 192 m ل

2 96 m J

3 384 m d

4 768 m ل

**NCERT-XI-I-83**

TEST SERIES (PHYSICS FST)

266419 The primary winding of tranformer has 500 turns whereas its secondary has 5000 turns. The primary is connected to an AC supply of $20 V - 50 Hz$ . The secondary will have an output of :

1

2 V, 5 Hz

2

200 V, 500 Hz

3

2 V, 50 Hz

4

200 V, 50 Hz

Explanation:

d
$\begin{aligned} \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ V_{s} = \frac{N_{S}}{N_{F}} V_{P} = \frac{5000}{500} \times 20 = 200 V \end{aligned}$

**NCERT-XII-I-194**

TEST SERIES (PHYSICS FST)

266420 A body of mass $m$ is suspended from a string of length I. What is minimum horizontal velocity that should be given to the body in its lowest position so that it may complete one full revolution in the vertical plane with the point of suspension as the centre of the circle

1

v = \sqrt{2 \lg}

2

v = \sqrt{319}

3

v = \sqrt{4 ∣ g}

4

v = \sqrt{5 \lg}

**NCERT-XI-I-63**

TEST SERIES (PHYSICS FST)

266421 On increasing the temperature of a conductor, its resistance increase because

1 Relaxation time decreases

2 Mass of the electrons increases

3 Electron density decreases

4 None of these

Explanation:

a
On increasing the temperature thermal speed of free electrons increase hence relaxation time decreases, and so resistance increases.
$as R = (\frac{m}{π r^{2} τ}) \frac{ℓ}{A}$

**NCERT-XII-I-90**

TEST SERIES (PHYSICS FST)

266422 A thin equiconvex lens has focal length 10 cm and refractive index 1.5. One of its faces is now silvered and for an objet placed at a distance $u$ in from of it, the image coincides with the object. The value of $u$ is

1 10 cm

2 5 cm

3 20 cm

4 15 cm

Explanation:

b
$\begin{aligned} \frac{1}{f} = \frac{μ - 1}{2 R} \\ \frac{1}{10} = \frac{0.5}{2 R} \\ R = 10 cm \end{aligned}$

$\begin{aligned} \frac{1}{f_{e q}} = \frac{- 2}{f_{L}} + \frac{1}{f_{m}} = - \frac{2}{10} + \frac{1}{+ 5} \\ f_{r} = 2.5 cm \\ u = 2 f_{r} = - 5 cm \end{aligned}$

**NCERT-XII-II-232**

TEST SERIES (PHYSICS FST)

266423 A bomb of mass 3 m kg explodes into two pieces of mass m kg and 2 m kg . If the velocity of m kg mass is $16 m / s$ , the total kinetic energy released in the explosion is

1 192 m ل

2 96 m J

3 384 m d

4 768 m ل

**NCERT-XI-I-83**

TEST SERIES (PHYSICS FST)

266419 The primary winding of tranformer has 500 turns whereas its secondary has 5000 turns. The primary is connected to an AC supply of $20 V - 50 Hz$ . The secondary will have an output of :

1

2 V, 5 Hz

2

200 V, 500 Hz

3

2 V, 50 Hz

4

200 V, 50 Hz

Explanation:

d
$\begin{aligned} \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ \frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{F}} \\ V_{s} = \frac{N_{S}}{N_{F}} V_{P} = \frac{5000}{500} \times 20 = 200 V \end{aligned}$

**NCERT-XII-I-194**

TEST SERIES (PHYSICS FST)

266420 A body of mass $m$ is suspended from a string of length I. What is minimum horizontal velocity that should be given to the body in its lowest position so that it may complete one full revolution in the vertical plane with the point of suspension as the centre of the circle

1

v = \sqrt{2 \lg}

2

v = \sqrt{319}

3

v = \sqrt{4 ∣ g}

4

v = \sqrt{5 \lg}

**NCERT-XI-I-63**

TEST SERIES (PHYSICS FST)

266421 On increasing the temperature of a conductor, its resistance increase because

1 Relaxation time decreases

2 Mass of the electrons increases

3 Electron density decreases

4 None of these

Explanation:

a
On increasing the temperature thermal speed of free electrons increase hence relaxation time decreases, and so resistance increases.
$as R = (\frac{m}{π r^{2} τ}) \frac{ℓ}{A}$

**NCERT-XII-I-90**

TEST SERIES (PHYSICS FST)

266422 A thin equiconvex lens has focal length 10 cm and refractive index 1.5. One of its faces is now silvered and for an objet placed at a distance $u$ in from of it, the image coincides with the object. The value of $u$ is

1 10 cm

2 5 cm

3 20 cm

4 15 cm

Explanation:

b
$\begin{aligned} \frac{1}{f} = \frac{μ - 1}{2 R} \\ \frac{1}{10} = \frac{0.5}{2 R} \\ R = 10 cm \end{aligned}$

$\begin{aligned} \frac{1}{f_{e q}} = \frac{- 2}{f_{L}} + \frac{1}{f_{m}} = - \frac{2}{10} + \frac{1}{+ 5} \\ f_{r} = 2.5 cm \\ u = 2 f_{r} = - 5 cm \end{aligned}$

**NCERT-XII-II-232**

TEST SERIES (PHYSICS FST)

266423 A bomb of mass 3 m kg explodes into two pieces of mass m kg and 2 m kg . If the velocity of m kg mass is $16 m / s$ , the total kinetic energy released in the explosion is

1 192 m ل

2 96 m J

3 384 m d

4 768 m ل

**NCERT-XI-I-83**