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968 Questions Start Allen Test
All Exams Allen Advance Errorless
Q326 Allen Newtons Laws of Motion MCQ
A girl pushes her physics book up against the horizontal ceiling of her room as shown in the figure. The book weighs 20 N and she pushes upwards with a force of 25 N. The choices below Column the magnitudes of the contact force $F_{CB}$ between the ceiling and the book, and $F_{BH}$ between the book and her hand. Select the correct pair. image.png
A.
$F_{CB} = 20N$ and $F_{BH} = 25N$
B.
$F_{CB} = 25N$ and $F_{BH} = 45N$
C.
$F_{CB} = 5N$ and $F_{BH} = 25N$
D.
$F_{CB} = 5N$ and $F_{BH} = 45N$
Q327 Allen Newtons Laws of Motion MCQ
Two astronauts A and B connected with a rope stay stationary in free space relative to their spaceship. Mass of A is more than that of B and the rope is straight. Astronaut A starts pulling the rope but astronaut B does not. If you were the third astronaut in the spaceship, what do you observe?
A.
Astronaut B accelerates towards A and A remains stationery.
B.
Both accelerate towards each other with equal accelerations of equal modulus.
C.
Both accelerate towards each other but acceleration of B is greater than that of A.
D.
Both accelerate towards each other but acceleration of B is smaller than that of A.
Q328 Allen Newtons Laws of Motion MCQ
Under what condition(s) will an object be in equilibrium?
A.
Only if it is at rest
B.
Only if it is moving with constant velocity
C.
Only if it is moving with constant acceleration
D.
If it is either at rest or moving with constant velocity
Q329 Allen Newtons Laws of Motion MCQ
All three blocks placed on horizontal surface at rest than net force on the middle block is?
A.
$30N$
B.
$40N$
C.
$90N$
D.
$0N$
Q330 Allen Newtons Laws of Motion MCQ
In a given figure system is in equilibrium. If $W_{1} = 300 \, N$ . Then $W_{2}$ is approximately equal to
A.
$500 N$
B.
$400N$
C.
$670N$
D.
$300N$
Q331 Allen Newtons Laws of Motion MCQ
Normal force acting between the blocks will be:
A.
$\frac{F}{3}$
B.
$\frac{F}{6}$
C.
$\frac{F}{4}$
D.
$\frac{2F}{3}$
Q332 Allen Newtons Laws of Motion MCQ
Two balls A and B weighing 7 N and 9 N are connected by a light cord. The system is suspended from a fixed support by connecting the ball A with another light cord. The ball B is pulled aside by a horizontal force 12 N and equilibrium is established. Angles $\alpha$ and $\beta$ respectively are
A.
$30^{\circ}$ and $60^{\circ}$ and
$6 0 ^ {\circ}$
B.
$6 0 ^ {\circ}$ and $3 0 ^ {\circ}$
C.
$37^{\circ}$ and $53^{\circ}$
D.
$53^{\circ}$ and $37^{\circ}$
Q333 Allen Newtons Laws of Motion MCQ
Two masses m and M are attached to strings as shown in the figure. In equilibrium $\tan \theta$ is :
A.
$1+(2M/m)$
B.
$1 + (2m / M)$
C.
$1 + (M / 2m)$
D.
None of these
Q334 Allen Newtons Laws of Motion MCQ
A perfect smooth sphere A of mass 2 kg is in contact with a rectangular block B of mass 4 kg and vertical wall as shown in the figure. All surfaces are smooth. Find normal reaction by vertical wall on sphere A
A.
$20N$
B.
$25N$
C.
$80N$
D.
$45N$
Q335 Allen Newtons Laws of Motion MCQ
In a hemispherical bowl of radius 8R, two balls of mass 5 kg are placed in the equilibrium. Radius of the ball is 3R. Normal contact force between the two balls is given by
A.
$\frac{75}{2}$
B.
$\frac{75}{4}$
C.
$\frac{75}{6}$
D.
15
Q336 Allen Newtons Laws of Motion MCQ
Three identical blocks each of mass 20kg are connected by ideal strings and are being pulled along a horizontal frictionless table by a constant horizontal force F as shown in figure. What is the magnitude of force F if the tension in the string connecting blocks A and B is 60 N?
A.
60 N
B.
120 N
C.
180 N
D.
90 N
Q337 Allen Newtons Laws of Motion MCQ
A block of mass m is placed in contact with one end of a smooth tube of mass M (see figure). A horizontal force F acts on the tube in each case (i) and (ii). Then mark incorrect option :
A.
$a_{m} = 0$ and $a_{M} = \frac{F}{M}$ in (i)
B.
$a_{m} = a_{M} = \frac{F}{M + m}$ in (i)
C.
$a_{m} = a_{M} = \frac{F}{M + m}$ in (ii)
D.
Force on m is $\frac{mF}{M+m}$ in (ii)
Q338 Allen Newtons Laws of Motion MCQ
The arrangement shown in the figure is in equilibrium. What is the contact force (in N) between the block A and 2 kg block? $(g = 10 \, m/s^{2})$
A.
$70N$
B.
$100N$
C.
$30N$
D.
$50N$
Q339 Allen Newtons Laws of Motion MCQ
What should be the value of "m" so that 4kg block remains at rest :-
A.
3 kg
B.
4 kg
C.
1.5 kg
D.
2.5 kg
Q340 Allen Newtons Laws of Motion MCQ
Mark the INCORRECT statement(s): Magnitude of acceleration of both blocks is $8 \, m/s^{2}$
A.
tension in the string is 180 N
B.
acceleration of mass $10 \, kg$ is $8 \, m/s^{2}$ upward
C.
acceleration of mass $10 \, kg$ is $8 \, m/s^{2}$ downward
D.
acceleration of mass $40 \, kg$ is $8 \, m/s^{2}$ downward
Q341 Allen Newtons Laws of Motion MCQ
All pulleys and strings are massless, for what ratio of $m_{1}: m_{2}: m_{3}$ system will be in equilibrium (inclined is frictionless)
A.
1:2:1
B.
2:2:1
C.
1:2:2
D.
2:1:2
Q342 Allen Newtons Laws of Motion MCQ
A force F is applied to the initially stationary cart. The variation of force with time is shown in the figure. The speed of cart at t = 5 second is :-
A.
$10 \mathrm{~m} / \mathrm{s}$
B.
8.33 m/s
C.
2 m/s
D.
zero
Q343 Allen Newtons Laws of Motion MCQ
Curve between net force vs time is shown.-Initially particle is at rest. Which of the following best represents the resulting velocity - time graph of the particle?
A.
B.
C.
D.
Q344 Allen Newtons Laws of Motion MCQ
In a given figure a block is kept on the fixed wedge. A force of magnitude F is acting on the block such that it makes angle $\theta$ with the inclined plane. Now $\theta$ is changing from 0 to 180Ā° then graph between normal reaction between block and wedge (N) and $\theta$ is :-
A.
B.
C.
D.
Q345 Allen Newtons Laws of Motion MCQ
A smooth pulley P of mass M = 2 kg is lying on a smooth table. A light string passes round the pulley and has mass m = 1kg and $m' = 2kg$ attached to its ends, the two portions of the string being perpendicular to the edge of the table so that the masses hang vertically. Acceleration of pulley is-
A.
$\frac{g}{2}$
B.
$\frac{2g}{3}$
C.
$\frac{4g}{9}$
D.
$\frac{4g}{7}$
Q346 Allen Newtons Laws of Motion MCQ
With what acceleration 'a' shown the elevator descends so that the block of mass M exerts a force of $\frac{Mg}{10}$ on the weighing machine? [g = acceleration due to gravity]
A.
0.3 g
B.
0.1 g
C.
0.9 g
D.
0.6 g
Q347 Allen Newtons Laws of Motion MCQ
The wedge of mass M sits at rest on a scale as shown in figure. A small block of mass m slides down the frictionless incline of the wedge. The scale reading while the block slides, is
A.
$(m + M) g$
B.
$M g + m g \cos^ {2} \theta$
C.
$(m + M)g + mg\sin^2\theta$
D.
$(M - m) g + m g \sin^ {2} \theta$
Q348 Allen Newtons Laws of Motion MCQ
The block is released from rest with the unstretched positions of springs initially. The acceleration of the block just after released will be $(g = 10 \, m/s^{2})$
A.
Zero
B.
$10m / s^2$ upwards
C.
$10m / s^2$ downward
D.
$5m / s^2$ upwards
Q349 Allen Newtons Laws of Motion MCQ
A sphere of mass 'm' is kept in equilibrium with the help of several springs as shown in the figure. Measurements show that one of the springs applies a force $\vec{F}$ on the sphere. With what acceleration the sphere will move immediately after this particular spring is cut?
A.
Zero
B.
$\frac{\vec{F}}{m}$
C.
$-\frac{\vec{F}}{m}$
D.
Insufficient information
Q350 Allen Newtons Laws of Motion MCQ
Two blocks A and B of equal mass 2 kg are arranged as shown with springs $S_{1}$ and $S_{2}$ . Spring $S_{2}$ is pulled with force F = 6 N. Acceleration of block B is 4 m/s $^{2}$ towards right at an instant. If F is suddenly removed at this instant, the instantaneous acceleration of A and B will be (Assume no friction)
A.
$a_{A} = 1 \, m/s^{2}$ towards right and $a_{B} = 4 \, m/s^{2}$ left
B.
$a_{A} = 1 \, m/s^{2}$ towards left and $a_{B} = 4 \, m/s^{2}$ right
C.
$a_{A} = 1m / s^{2}$ towards left and $a_{B} = 1m / s^{2}$ right
D.
$a_{A}=0$ and $a_{B}=4\ m/s^{2}$ right