Physics MCQs thread.

[arlery]

It's because the direction of electric field will be from the more positive plate to the less positive plate.

 

[airborne1944]

Hey guys need help PLEASE.

Q21 http://www.xtremepapers.me/CIE/Internat ... 5_qp_1.pdf

Q29 http://www.xtremepapers.me/CIE/Internat ... 6_qp_1.pdf

Need help, thx!

29 ka ans is B

Care to explain? I don't understand in getting the answer.

 

[Hateexams93]

Two springs P and Q both obey Hooke’s law. They have spring constants 2k and k respectively.
The springs are stretched, separately, by a force that is gradually increased from zero up to a
certain maximum value, the same for each spring. The work done in stretching spring P is WP,
and the work done in stretching spring Q is WQ.
How is WP related to WQ?
A WP =
 0.25WQ B WP = 0.5
 WQ C WP = 2WQ D WP = 4WQ

hey first find f for both using f=kx x iz same for both
then use wd =1/2fx

i did and i got C , but its wrong

 

[hassam]

A tuning fork of pitch 2.4 kHz is placed near the mouth of a long cylindrical container
which is fully filled with water. Water is slowly drained from the bottom of the container.
Resonance is first heard when the water level had dropped 3.4 cm below the mouth of
the container. At which position of water below the mouth of the container will the next
resonance be heard? Assume the speed of sound in air = 3.4 x 102 m s-1.
A 7.1 cm
B 8.0 cm
C 10.2 cm
D 10.5 cm

 

[minnienerd]

qn 21 ans is C as-----d sin Q= n lamda
1.15*10^-6 *sin (60/2)= 1 * lamda (n= 1 for monochromatic light)
so wavelength = 575 nm ....hope this helps

 

[hassam]

ZISHIIII ans the questionnn......

 

[arlery]

A parallel beam of light of wavelength 450 nm falls normally on a diffraction grating which has
300 lines / mm.
What is the total number of transmitted maxima?
A 7
B 8
C 14
D 15

 

[unique840]

Hey guys need help PLEASE.

Q21 http://www.xtremepapers.me/CIE/Internat ... 5_qp_1.pdf

Q29 http://www.xtremepapers.me/CIE/Internat ... 6_qp_1.pdf

Need help, thx!

29 ka ans is B

Care to explain? I don't understand in getting the answer.

direction of electric field is frm more +ve to less +ve. n the first n last line of field always bulges outward.

 

[histephenson007]

A tuning fork of pitch 2.4 kHz is placed near the mouth of a long cylindrical container
which is fully filled with water. Water is slowly drained from the bottom of the container.
Resonance is first heard when the water level had dropped 3.4 cm below the mouth of
the container. At which position of water below the mouth of the container will the next
resonance be heard? Assume the speed of sound in air = 3.4 x 102 m s-1.
A 7.1 cm
B 8.0 cm
C 10.2 cm
D 10.5 cm

Is the answer C?

 

[unique840]

A parallel beam of light of wavelength 450 nm falls normally on a diffraction grating which has
300 lines / mm.
What is the total number of transmitted maxima?
A 7
B 8
C 14
D 15

total maxima = 2*highest maxima +1
highest maxima = line spacing/wavelenght
line spacing = 1/300*10^3
wavelenght = 450nm

 

[yubakkk]

Two springs P and Q both obey Hooke’s law. They have spring constants 2k and k respectively.
The springs are stretched, separately, by a force that is gradually increased from zero up to a
certain maximum value, the same for each spring. The work done in stretching spring P is WP,
and the work done in stretching spring Q is WQ.
How is WP related to WQ?
A WP =
 0.25WQ B WP = 0.5
 WQ C WP = 2WQ D WP = 4WQ

hey first find f for both using f=kx x iz same for both
then use wd =1/2fx

i did and i got C , but its wrong

its ans is c its alright

 

[minnienerd]

@hassam..is the ans C ?

 

[Zishi]

A tuning fork of pitch 2.4 kHz is placed near the mouth of a long cylindrical container
which is fully filled with water. Water is slowly drained from the bottom of the container.
Resonance is first heard when the water level had dropped 3.4 cm below the mouth of
the container. At which position of water below the mouth of the container will the next
resonance be heard? Assume the speed of sound in air = 3.4 x 102 m s-1.
A 7.1 cm
B 8.0 cm
C 10.2 cm
D 10.5 cm

D

 

[melon159]

got D

 

[unique840]

A tuning fork of pitch 2.4 kHz is placed near the mouth of a long cylindrical container
which is fully filled with water. Water is slowly drained from the bottom of the container.
Resonance is first heard when the water level had dropped 3.4 cm below the mouth of
the container. At which position of water below the mouth of the container will the next
resonance be heard? Assume the speed of sound in air = 3.4 x 102 m s-1.
A 7.1 cm
B 8.0 cm
C 10.2 cm
D 10.5 cm

D

me ka b D cuming

 

[yubakkk]

use eng languaege ok u hassan

 

[minnienerd]

can u explain why is it D ??

 

[unique840]

can u explain why is it D ??

wavelenght=speed/frequency
second resonance occurs at 3/4 of wavelenght
ull get the answer. change the answer from metres to cm

 

[MW24595]

Hmm, what about May/June 2004 Questions 15 and 27? Help is appreciated.
With Question 15, the net moment should be 40Nm anticlockwise, but it's apparently clockwise in the mark scheme.

 

[arlery]

How can I solve this?