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Kinematics-2D

362 Questions Start Errorless Test
All Exams Allen Advance Errorless
Basic Level Q101 Errorless Angular Velocity MCQ
The ratio of an angular speed of hours hand and seconds hand of a clock is 210 Motion In Two Dimension
A.
1 : 1
B.
1 : 60
C.
1 : 720
D.
3600 : 1
Advance Level Q102 Errorless Angular Velocity MCQ
A racing car is travelling along a track at a constant speed of 40 m/s. A T.V. camera men is recording the event from a distance of 30m directly away from the track as shown in figure. In order to keep the car under view in the position shown, the angular speed with which the camera sh
A.
4/3 rad/sec
B.
3/4 rad/sec
C.
8/3 $\sqrt{3}$ rad/sec
D.
1 rad/sec
Advance Level Q103 Errorless Angular Velocity MCQ
A particle is moving along a circular path with angular speed $\omega$ about the axis passing through the centre. What will be its angular speed about a point on the other end of the diameter through the instantaneous position of the particle
A.
$2\omega$
B.
$\omega$
C.
$\omega/2$
D.
$\omega/4$
Basic Level Q104 Errorless Velocity MCQ
The linear velocity of a point on the equator is nearly (radius of the earth is 6400 km)
A.
800 km/hr
B.
1600 km/hr
C.
3200 km/hr
D.
6400 km/hr
Basic Level Q105 Errorless Velocity MCQ
The second's hand of a watch has length 6 cm. Speed of end point and magnitude of difference of velocities at two perpendicular positions will be
A.
6.28 and 0 mm/s
B.
8.88 and 4.44 mm/s
C.
8.88 and 6.28 mm/s
D.
6.28 and 8.88 mm/s
Advance Level Q106 Errorless Velocity MCQ
An aeroplane is moving in a horizontal circle with a uniform speed of 141 km/hr. Change in its velocity in one fourth revolution, from its initial direction will be
A.
100 km/hr at an angle of $90^{\circ}$
B.
141 km/hr at an angle of $135^{\circ}$
C.
200 km/hr at an angle of $135^{\circ}$
D.
Zero
Basic Level Q107 Errorless Angular Accelerations MCQ
The linear and angular acceleration of a particle are $10 \, m/sec^{2}$ and $5 \, rad/sec^{2}$ respectively it will be at a distance from the axis of rotation
A.
50 m
B.
$1/2 \, m$
C.
1 m
D.
2 m
Basic Level Q108 Errorless Angular Accelerations MCQ
On applying brakes the angular velocity of a flywheel reduces from 900 cycles/min to 720 cycles/min in 6 seconds. Its angular retardation in $rad/s^2$ will be
A.
$\pi/3$
B.
$\pi$
C.
$2\pi/3$
D.
$2\pi$
Advance Level Q109 Errorless Angular Accelerations MCQ
A particle is moving in a circular path with velocity varying with time as $v = 1.5 t^{2} + 2t$ . If 2cm the radius of circular path, the angular acceleration at t = 2 sec will be
A.
$4 rad/sec^{2}$
B.
$40 rad/sec^{2}$
C.
$400 rad/sec^{2}$
D.
$0.4 rad/sec^{2}$
Basic Level Q110 Errorless Centripetal Acceleration MCQ
A stone, tied at the end of a string 80 cm long, is whirled in a horizontal circle with a constant speed. If the stone makes 14 revolutions in 25 sec, what is the magnitude of acceleration of the stone
A.
$680 \, cm/s^{2}$
B.
$720 \, cm/s^{2}$
C.
$860 \, cm/s^{2}$
D.
$990 \, cm/s^{2}$
Basic Level Q111 Errorless Centripetal Acceleration MCQ
What happens to the centripetal acceleration of a revolving body if you double the orbital speed v and half the angular velocity $\omega$
A.
The centripetal acceleration remains unchanged
B.
The centripetal acceleration is halved
C.
The centripetal acceleration is doubled
D.
The centripetal acceleration is quadrupled
Basic Level Q112 Errorless Centripetal Acceleration MCQ
The mean distance of the moon from the earth is $3.84 \times 10^{8} m$ . The moon makes one revolution round the earth in $2.34 \times 10^{6}$ sec. The acceleration of the moon towards the earth is
A.
$2.73 \times 10^{-3} m/s^{2}$
B.
$2.73 \times 10^{-2} m/s^{2}$
C.
$0.273 m/s^{2}$
D.
$2.73 \times 10^{-4} m/s^{2}$
Advance Level Q113 Errorless Centripetal Acceleration MCQ
An astronaut is rotating in a rotor of radius $4m$ . If he can withstand maximum acceleration of $10g$ , the maximum permissible frequency of rotor will be
A.
$\frac{\pi}{5} Hz$
B.
$\frac{2\pi}{5} Hz$
C.
$\frac{5\pi}{5} Hz$
D.
$\frac{5}{2\pi} Hz$
Q114 Errorless Centripetal and Centrifugal Force MCQ
Two masses M and m are attached to a vertical axis by weightless threads of combined length L. They are set in rotational motion in a horizontal plane about this axis with constant angular velocity $\omega$ . If the tensions in the threads are the same during motion, the distance of M from the axis is
A.
$\frac{Ml}{M+m}$
B.
$\frac{ml}{M+m}$
C.
$\frac{M+m}{M}l$
D.
$\frac{M+m}{m}l$
Q115 Errorless Centripetal and Centrifugal Force MCQ
In the Bohr model of a hydrogen atom, the centripetal force is furnished by the coulomb attraction between the proton and the electron. If $a_0$ is the radius of the ground state orbit, $m$ is the mass, $e$ is the charge on the electron and $\varepsilon_0$ is the vacuum permittivity, then speed of the electron is
A.
$\sqrt{\frac{\varepsilon_0a_0m}{e}}$
B.
$\frac{e}{\sqrt{\varepsilon_0a_0m}}$
C.
$\frac{\sqrt{4\pi\varepsilon_0a_0m}}{e}$
D.
$\frac{e}{\sqrt{4\pi\varepsilon_0a_0m}}$
Q116 Errorless Centripetal and Centrifugal Force MCQ
A rubber band of length l has a stone of mass m tied to its one end. It is whirled with speed v so that the stone describes a horizontal circular path. The tension T in the rubber band is
A.
Zero
B.
$mv^{2}/l$
C.
$>(mv^{2})/l$
D.
$
Q117 Errorless Centripetal and Centrifugal Force MCQ
A particle of mass m is executing uniform circular motion on a path of radius r. If p is the magnitude of its linear momentum. The radial force acting on the particle is
A.
pmr
B.
$\frac{rm}{p}$
C.
$\frac{mp^{2}}{r}$
D.
$\frac{p^{2}}{rm}$
Q118 Errorless Centripetal and Centrifugal Force MCQ
Two particles of equal masses are revolving in circular paths of radii $r_1$ and $r_2$ respectively with the same speed. The ratio of their centripetal forces is
A.
$\frac{r_2}{r_1}$
B.
$\sqrt{\frac{r_2}{r_1}}$
C.
$\left(\frac{r_1}{r_2}\right)^2$
D.
$\left(\frac{r_2}{r_1}\right)^2$
Q119 Errorless Centripetal and Centrifugal Force MCQ
A particle of mass m is observed from an inertial frame of reference and is forced to move in a circle of radius r with a uniform speed v. The centrifugal force on it is
A.
$\frac{mv^{2}}{r}$ towards the centre
B.
$\frac{mv^{2}}{r}$ away from the centre
C.
$\frac{mv^{2}}{r}$ along the tangent through the particle
D.
Zero
Q120 Errorless Centripetal and Centrifugal Force MCQ
A bowl, containing water and mercury, is revolved rapidly about a vertical axis, then the liquid which remains outermost is
A.
Water
B.
Mercury
C.
Mercury and water both
D.
None of the above
Q121 Errorless Centripetal and Centrifugal Force MCQ
The tube AB forms a quarter circle in a vertical plane. The particle Pcan move without friction in the tube. P is placed at A and displaced slightly. It will
A.
Always be in contact with the outer wall
B.
Always be in contact with the inner wall
C.
Initially be in contact with the inner wall and later with the outer wall
D.
Initially be in contact with the outer wall and later with the inner wall
Q122 Errorless Centripetal and Centrifugal Force MCQ
A small block of mass 0.1kg moves with uniform speed in a horizontal circular groove of radius 1m. The block takes $\pi$ sec to complete one round. The normal contact force by the side will be
A.
0.25 N
B.
0.4 N
C.
0.56 N
D.
0.1 N
Advance Level Q123 Errorless Centripetal and Centrifugal Force MCQ
A particle of mass $m_{1}$ is fastened to one end of a string and one of $m_{2}$ to the middle point, the other end of the string being fastened to a fixed point on a smooth horizontal table. The particles are then projected, so that the two portions of the string are always in the same straight line and describes horizontal circles. Find the ratio of tensions in the two parts of the string
A.
$\frac{m_{1}}{m_{1}+m_{2}}$
B.
$\frac{m_{1}+m_{2}}{m_{1}}$
C.
$\frac{2m_{1}+m_{2}}{2m_{1}}$
D.
$\frac{2m_{1}}{m_{1}+m_{2}}$
Advance Level Q124 Errorless Centripetal and Centrifugal Force MCQ
A toy cart is tied to the end of an unstretched string of length $a$ . When revolved, thy toy cart moves in a horizontal circle of radius $2a$ with a time period $T$ . Now the toy cart is speeded up until it moves in a horizontal circle of radius $3a$ with a period $T'$ . If Hooke's law holds, then
A.
$T' = T$
B.
$T' = (3/2)T$
C.
$T' = (\sqrt{3}/2)T$
D.
$T' = \sqrt{(3/2)}T$
Advance Level Q125 Errorless Centripetal and Centrifugal Force MCQ
A chain of 125 links is $1.25m$ long and has a mass of $2kg$ . With the ends fastened together it is set rotating at $3000 \text{ rev/min}$ . Find the centripetal force on each link
A.
$3.14N$
B.
$314 N$
C.
$\frac{1}{3.14} N$
D.
$\frac{1}{314} N$