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List of top Physics Questions asked in JEE Main
The height of any point P above the surface of earth is equal to diameter of earth. The value of acceleration due to gravity at point P will be (Given g = acceleration due to gravity at the surface of earth).
JEE Main - 2022
JEE Main
Physics
Gravitation
The approximate height from the surface of the earth at which the weight of the body becomes
\(\frac{1}{3}\)
of its weight on the surface of earth is [Radius of earth
R
= 6400 km and √3=1.732]
JEE Main - 2022
JEE Main
Physics
Gravitation
Given below are two statements.
Statement-I:
The law of gravitation holds good for any pair of bodies in the universe.
Statement-II:
The weight of any person becomes zero when the person is at the centre of the earth.
In the light of the above statements, choose the
correct
answer from the options given below
JEE Main - 2022
JEE Main
Physics
Gravitation
Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A
: If we move from poles to equator, the direction of acceleration due to gravity of earth always points towards the center of earth without any variation in its magnitude.
Reason R
: At equator, the direction of acceleration due to the gravity is towards the center of earth.
In the light of above statements, choose the correct answer from the options given below
JEE Main - 2022
JEE Main
Physics
Gravitation
A ball of mass
\(0.15\)
\(kg\)
hits the wall with its initial speed of
\(12\)
\(ms^{–1}\)
and bounces back without changing its initial speed. If the force applied by the wall on the ball during the contact is
\(100\)
\(N\)
, calculate the time duration of the contact of ball with the wall.
JEE Main - 2022
JEE Main
Physics
Gravitation
A body is projected vertically upwards from the surface of earth with a velocity equal to one third of escape velocity. The maximum height attained by the body will be:
JEE Main - 2022
JEE Main
Physics
Gravitation
The percentage decrease in the weight of a rocket, when taken to a height of 32 km above the surface of earth will, be:
(Radius of earth = 6400 km)
JEE Main - 2022
JEE Main
Physics
Gravitation
Two planets
A
and
B
of equal mass are having their period of revolutions
T
A
and
T
B
such that
T
A
= 2
T
B
. These planets are revolving in the circular orbits of radii
r
A
and
r
B
respectively. Which out of the following would be the correct relationship of their orbits?
JEE Main - 2022
JEE Main
Physics
Gravitation
The time period of a satellite revolving around earth in a given orbit is 7 hours. If the radius of orbit is increased to three times its previous value, then approximate new time period of the satellite will be
JEE Main - 2022
JEE Main
Physics
Gravitation
The area of cross section of the rope used to lift a load by a crane is
\(2.5 × 10^{–4}\)
\(m^2\)
. The maximum lifting capacity of the crane is
\(10\)
metric tons. To increase the lifting capacity of the crane to
\(25\)
metric tons, The required area of cross section of the rope should be
JEE Main - 2022
JEE Main
Physics
Gravitation
The variation of acceleration due to gravity (g) with distance (r) from the center of the earth is correctly represented by
(Given R = radius of earth)
JEE Main - 2022
JEE Main
Physics
Gravitation
A ball of mass 0.5 kg is dropped from the height of 10 m. The height, at which the magnitude of velocity becomes equal to the magnitude of acceleration due to gravity, is ___ m.
[Use g = 10 m/s
2
]
JEE Main - 2022
JEE Main
Physics
Gravitation
The elongation of a wire on the surface of the earth is 10
–4
m. The same wire of same dimensions is elongated by 6 × 10
–5
m on another planet. The acceleration due to gravity on the planet will be ___ ms
–2
. (Take acceleration due to gravity on the surface of earth = 10 ms
–2
)
JEE Main - 2022
JEE Main
Physics
Gravitation
A body of mass
m
is projected with velocity λ
v
e
in vertically upward direction from the surface of the earth into space. It is given that
v
e
is escape velocity and λ< 1. If air resistance is considered to be negligible, then the maximum height from the centre of earth, to which the body can go, will be:
(R : radius of earth)
JEE Main - 2022
JEE Main
Physics
Gravitation
Two objects of equal masses placed at certain distance from each other attracts each other with a force of F. If one-third mass of one object is transferred to the other object, then the new force will be
JEE Main - 2022
JEE Main
Physics
Gravitation
As shown in the figure, after passing through the medium 1. The speed of light v
2
in medium 2 will be: (Given
\(c = 3 \times 10^8 ms^{-1}\)
)
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
In normal adjustment, for a refracting telescope, the distance between objective and eye piece is $30\,cm$ The focal length of the objective, when the angular magnification of the telescope is 2, will be:
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
A light wave travelling linearly in a medium of dielectric constant 4, incidents on the horizontal interface separating medium with air. The angle of incidence for which the total intensity of incident wave will be reflected back into the same medium will be:
(Given : relative permeability of medium μ
r
= 1)
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
A signal of 100 THz frequency can be transmitted with maximum efficiency by :
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
The difference of speed of light in the two media A and B(υ
A
– υ
B
) is 2.6 × 10
7
m/s. If the refractive index of medium B is 1.47, then the ratio of refractive index of medium B to medium A is: (Given: speed of light in vacuum C = 3 × 10
8
ms
–1
)
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
A parallel beam of light of wavelength 900 nm and intensity 100 Wm
–2
is incident on a surface perpendicular to the beam. The number of photons crossing 1 cm
–2
area perpendicular to the beam in one second is
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
The refracting angle of prism is A and refractive index of material of prism is
$\cot \frac{A}{2}$
The angle of minimum deviation is
KCET - 2020
KCET
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
The aperture of the objective is 24.4 cm. The resolving power of this telescope, if a light of wavelength 2440 Å is used to see the object will be:
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
A small bulb is placed at the bottom of a tank containing water to a depth of √7 m. The refractive index of water is 4/3. The area of the surface of water through which light from the bulb can emerge out is
x
π m
2
. The value of
x
is ________.
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
The power of a lens (biconvex) is
\(1.25 m^{–1}\)
in particular medium. Refractive index of the lens is
\(1.5\)
, and the radii of curvature are
\(20 cm\)
and
\(40 cm\)
, respectively. The refractive index of surrounding medium
JEE Main - 2022
JEE Main
Physics
Ray optics and optical instruments
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