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Question Number 20992 Answers: 3 Comments: 1

Question Number 20986 Answers: 1 Comments: 1

A 50 kg log rest on the smooth horizontal surface. A motor deliver a towing force T as shown below. The momentum of the particle at t = 5 s is

$A 50 kg \log rest on the smooth horizontal$ $surface . A motor deliver a towing force$ $T as shown below . The momentum of$ $the particle at t = 5 s is$

Question Number 20984 Answers: 1 Comments: 1

A ball of mass m is moving with a velocity u rebounds from a wall with same speed. The collision is assumed to be elastic and the force of interaction between the ball and the wall varies as shown in the figure given below. The value of F_m is

$A ball of mass m is moving with a$ $velocity u rebounds from a wall with$ $same speed . The collision is assumed$ $to be elastic and the force of interaction$ $between the ball and the wall varies as$ $shown in the figure given below . The$ $value of F_{m} is$

Question Number 20936 Answers: 1 Comments: 1

A graph of x versus t is shown in Figure. Choose correct alternatives from below. (a) The particle was released from rest at t = 0 (b) At B, the acceleration a > 0 (c) At C, the velocity and the acceleration vanish (d) Average velocity for the motion between A and D is positive (e) The speed at D exceeds that at E.

$A graph of x versus t is shown in Figure .$ $Choose correct alternatives from below .$ $(a) The particle was released from$ $rest at t = 0$ $(b) At B, the acceleration a > 0$ $(c) At C, the velocity and the$ $acceleration vanish$ $(d) Average velocity for the motion$ $between A and D is positive$ $(e) The speed at D exceeds that at E .$

Question Number 20916 Answers: 1 Comments: 0

A body starts rotating about a stationary axis with an angular acceleration b = 2t rad/s^2 . How soon after the beginning of rotation will the total acceleration vector of an arbitrary point on the body forms an angle of 60° with its velocity vector? (1) (2(√3))^(1/3) s (2) (2(√3))^(1/2) s (3) (2(√3)) s (4) (2(√3))^2 s

$A body starts rotating about a$ $stationary axis with an angular$ $acceleration b = 2 t rad / s^{2} . How soon$ $after the beginning of rotation will the$ $total acceleration vector of an arbitrary$ $point on the body forms an angle of 60 °$ $with its velocity vector ?$ $(1) {(2 \sqrt{3})}^{1 / 3} s$ $(2) {(2 \sqrt{3})}^{1 / 2} s$ $(3) (2 \sqrt{3}) s$ $(4) {(2 \sqrt{3})}^{2} s$

Question Number 20915 Answers: 1 Comments: 0

Two shells are fired from a canon with speed u each, at angles of α and β respectively with the horizontal. The time interval between the shots is t. They collide in mid air after time T from the first shot. Which of the following conditions must be satisfied? (a) α > β (b) T cos α = (T − t) cos β (c) (T − t) cos α = T cos β (d) u sin α T − (1/2) g T^2 = u sin β (T − t) − (1/2) g (T − t)^2

$Two shells are fired from a canon with speed u each, at$ $angles of α and β respectively with the horizontal . The$ $time interval between the shots is t . They collide in mid$ $air after time T from the first shot . Which of the$ $following conditions must be satisfied ?$ $(a) α > β$ $(b) T \cos α = (T - t) \cos β$ $(c) (T - t) \cos α = T \cos β$ $(d) u \sin α T - \frac{1}{2} g T^{2} = u \sin β (T - t) - \frac{1}{2} g {(T - t)}^{2}$

Question Number 20891 Answers: 0 Comments: 11

The Figure shows a system consisting of (i) a ring of outer radius 3R rolling clockwise without slipping on a horizontal surface with angular speed ω and (ii) an inner disc of radius 2R rotating anti-clockwise with angular speed ω/2. The ring and disc are separated by frictionless ball bearing. The system is in the x-z plane. The point P on the inner disc is at a distance R from the origin, where OP makes an angle 30° with the horizontal. Then with respect to the horizontal surface (a) The point O has a linear velocity 3Rωi^∧ (b) The point P has a linear velocity ((11)/4)Rωi^∧ + ((√3)/4)Rωk^∧

$The Figure shows a system consisting$ $of (i) a ring of outer radius 3 R rolling$ $clockwise without slipping on a$ $horizontal surface with angular speed$ $ω and (i i) an inner disc of radius 2 R$ $rotating anti - clockwise with angular$ $speed ω / 2 . The ring and disc are$ $separated by frictionless ball bearing .$ $The system is in the x - z plane . The$ $point P on the inner disc is at a distance$ $R from the origin, where O P makes an$ $angle 30 ° with the horizontal . Then$ $with respect to the horizontal surface$ $(a) The point O has a linear velocity$ $3 R ω \overset{\land}{i}$ $(b) The point P has a linear velocity$ $\frac{11}{4} R ω \overset{\land}{i} + \frac{\sqrt{3}}{4} R ω \overset{\land}{k}$

Question Number 20842 Answers: 1 Comments: 0

Acceleration of a particle which is at rest at x = 0 is a^→ = (4 − 2x) i^∧ . Select the correct alternative(s). (a) Maximum speed of the particle is 4 units (b) Particle further comes to rest at x = 4 (c) Particle oscillates about x = 2 (d) Particle will continuously accelerate along the x-axis.

$Acceleration of a particle which is at$ $rest at x = 0 is \vec{a} = (4 - 2 x) \overset{\land}{i} . Select$ $the correct alternative (s) .$ $(a) Maximum speed of the particle is$ $4 units$ $(b) Particle further comes to rest at$ $x = 4$ $(c) Particle oscillates about x = 2$ $(d) Particle will continuously accelerate$ $along the x - axis .$

Question Number 20786 Answers: 2 Comments: 0

Two particles A and B start from the same position along the circular path of radius 0.5 m with a speed v_A = 1 ms^(−1) and v_B = 1.2 ms^(−1) in opposite direction. Determine the time before they collide.

$Two particles A and B start from the$ $same position along the circular path of$ $radius 0.5 m with a speed v_{A} = 1 {ms}^{- 1}$ $and v_{B} = 1.2 {ms}^{- 1} in opposite direction .$ $Determine the time before they collide .$

Question Number 20777 Answers: 0 Comments: 6

In the figure shown, mass ′m′ is placed on the inclined surface of a wedge of mass M. All the surfaces are smooth. Find the acceleration of the wedge.

$I n t h e f i g u r e s h o w n, m a s s^{'} m^{'} i s$ $p l a c e d o n t h e i n c l i n e d s u r f a c e o f a$ $w e d g e o f m a s s M . A l l t h e s u r f a c e s$ $a r e s m o o t h . F i n d t h e a c c e l e r a t i o n o f$ $t h e w e d g e .$

Question Number 20764 Answers: 1 Comments: 0

A small bead is slipped on a horizontal rod of length l. The rod starts moving with a horizontal acceleration a in a direction making an angle α with the length of the rod. Assuming that initially the bead is in the middle of the rod, find the time elapsed before the bead leaves the rod. Coefficient of friction between the bead and the rod is μ. (Neglect gravity).

$A s m a l l b e a d i s s l i p p e d o n a h o r i z o n t a l$ $r o d o f l e n g t h l . T h e r o d s t a r t s m o v i n g$ $w i t h a h o r i z o n t a l a c c e l e r a t i o n a i n a$ $d i r e c t i o n m a k i n g a n a n g l e α w i t h t h e$ $l e n g t h o f t h e r o d . A s s u m i n g t h a t$ $i n i t i a l l y t h e b e a d i s i n t h e m i d d l e o f$ $t h e r o d, f i n d t h e t i m e e l a p s e d b e f o r e$ $t h e b e a d l e a v e s t h e r o d . C o e f f i c i e n t o f$ $f r i c t i o n b e t w e e n t h e b e a d a n d t h e r o d$ $i s μ . (N e g l e c t g r a v i t y) .$

Question Number 20745 Answers: 1 Comments: 3

Consider a disc rotating in the horizontal plane with a constant angular speed ω about its centre O. The disc has a shaded region on one side of the diameter and an unshaded region on the other side as shown in the Figure. When the disc is in the orientation as shown, two pebbles P and Q are simultaneously projected at an angle towards R. The velocity of projection is in the y-z plane and is same for both pebbles with respect to the disc. Assume that (i) they land back on the disc before the disc has completed (1/8) rotation, (ii) their range is less than half the disc radius, and (iii) ω remains constant throughout. Then (a) P lands in the shaded region and Q in the unshaded region (b) P lands in the unshaded region and Q in the shaded region (c) Both P and Q land in the unshaded region (d) Both P and Q land in the shaded region

$Consider a disc rotating in the horizontal$ $plane with a constant angular speed ω$ $about its centre O . The disc has a$ $shaded region on one side of the diameter$ $and an unshaded region on the other$ $side as shown in the Figure . When the$ $disc is in the orientation as shown, two$ $pebbles P and Q are simultaneously$ $projected at an angle towards R . The$ $velocity of projection is in the y - z$ $plane and is same for both pebbles with$ $respect to the disc . Assume that (i) they$ $land back on the disc before the disc has$ $completed \frac{1}{8} rotation, (i i) their range$ $is less than half the disc radius, and$ $(i i i) ω remains constant throughout .$ $Then$ $(a) P lands in the shaded region and Q$ $in the unshaded region$ $(b) P lands in the unshaded region and$ $Q in the shaded region$ $(c) Both P and Q land in the unshaded$ $region$ $(d) Both P and Q land in the shaded$ $region$

Question Number 20724 Answers: 0 Comments: 3

A sphere is rolling without slipping on a fixed horizontal plane surface. In the Figure, A is a point of contact, B is the centre of the sphere and C is its topmost point. Then (a) v_C ^→ − v_A ^→ = 2(v_B ^→ − v_C ^→ ) (b) v_C ^→ − v_B ^→ = v_B ^→ − v_A ^→ (c) ∣v_C ^→ − v_A ^→ ∣ = 2∣v_B ^→ − v_C ^→ ∣ (d) ∣v_C ^→ − v_A ^→ ∣ = 4∣v_B ^→ ∣

$A sphere is rolling without slipping on$ $a fixed horizontal plane surface . In the$ $Figure, A is a point of contact, B is the$ $centre of the sphere and C is its topmost$ $point . Then$ $(a) {\vec{v}}_{C} - {\vec{v}}_{A} = 2 ({\vec{v}}_{B} - {\vec{v}}_{C})$ $(b) {\vec{v}}_{C} - {\vec{v}}_{B} = {\vec{v}}_{B} - {\vec{v}}_{A}$ $(c) ∣ {\vec{v}}_{C} - {\vec{v}}_{A} ∣ = 2 ∣ {\vec{v}}_{B} - {\vec{v}}_{C} ∣$ $(d) ∣ {\vec{v}}_{C} - {\vec{v}}_{A} ∣ = 4 ∣ {\vec{v}}_{B} ∣$

Question Number 20761 Answers: 0 Comments: 5

A 5 kg block B is suspended from a cord attached to a 40 kg cart A. Find the accelerations of both the block and cart. (All surfaces are frictionless) (g = 10 m/s^2 )

$A 5 k g b l o c k B i s s u s p e n d e d f r o m a$ $c o r d a t t a c h e d t o a 40 k g c a r t A . F i n d$ $t h e a c c e l e r a t i o n s o f b o t h t h e b l o c k a n d$ $c a r t . (A l l s u r f a c e s a r e f r i c t i o n l e s s)$ $(g = 10 m / s^{2})$

Question Number 20581 Answers: 0 Comments: 5

The surface between wedge and block is rough (Coefficient of friction μ). Find out the range of F such that, there is no relative motion between wedge and block. The wedge can move freely on smooth ground.

$T h e s u r f a c e b e t w e e n w e d g e a n d b l o c k$ $i s r o u g h (C o e f f i c i e n t o f f r i c t i o n μ) .$ $F i n d o u t t h e r a n g e o f F s u c h t h a t,$ $t h e r e i s n o r e l a t i v e m o t i o n b e t w e e n$ $w e d g e a n d b l o c k . T h e w e d g e c a n m o v e$ $f r e e l y o n s m o o t h g r o u n d .$

Question Number 20579 Answers: 0 Comments: 3

A 1 kg block is being pushed against a wall by a force F = 75 N as shown in the figure. The coefficient of friction is 0.25. The magnitude of acceleration of the block is

$A 1 kg block is being pushed against a$ $wall by a force F = 75 N as shown in$ $the figure . The coefficient of friction is$ $0.25 . The magnitude of acceleration of$ $the block is$

Question Number 20501 Answers: 0 Comments: 5

The force acting on the block is given by F = 5 − 2t. The frictional force acting on the block at t = 2 s. (The block is at rest at t = 0)

$The force acting on the block is given by$ $F = 5 - 2 t . The frictional force acting$ $on the block at t = 2 s . (The block is at$ $rest at t = 0)$

Question Number 20461 Answers: 0 Comments: 4

Question Number 20460 Answers: 0 Comments: 1

Question Number 20425 Answers: 1 Comments: 1

On a frictionless horizontal surface, assumed to be the x-y plane, a small trolley A is moving along a straight line parallel to the y-axis (see figure) with a constant velocity of ((√3) − 1) m/s. At a particular instant, when the line OA makes an angle of 45° with the x-axis, a ball is thrown along the surface from the origin O. Its velocity makes an angle φ with x-axis and it hits the trolley. 1. The motion of the ball is observed from the frame of the trolley. Calculate the angle θ made by the velocity vector of the ball with the x-axis in this frame. 2. Find the speed of the ball with respect to the surface, if φ = ((4θ)/3)

$On a frictionless horizontal surface,$ $assumed to be the x - y plane, a small$ $trolley A is moving along a straight$ $line parallel to the y - axis (see figure)$ $with a constant velocity of (\sqrt{3} - 1) m / s .$ $At a particular instant, when the line$ $O A makes an angle of 45 ° with the$ $x - axis, a ball is thrown along the$ $surface from the origin O . Its velocity$ $makes an angle ϕ with x - axis and it$ $hits the trolley .$ $1 . The motion of the ball is observed from$ $the frame of the trolley . Calculate the$ $angle θ made by the velocity vector of$ $the ball with the x - axis in this frame .$ $2 . Find the speed of the ball with$ $respect to the surface, if ϕ = \frac{4 θ}{3}$

Question Number 20412 Answers: 0 Comments: 3

A block is placed on a rough horizontal surface. The minimum force required to slide the block is

$A block is placed on a rough horizontal$ $surface . The minimum force required$ $to slide the block is$

Question Number 20411 Answers: 1 Comments: 0

A stone of weight W is thrown straight up from the ground with an initial speed u. if a drag force of constant magnitude f acts on the stone through out its flight, the speed of stone just before reaching the ground is

$A stone of weight W is thrown straight$ $up from the ground with an initial$ $speed u . if a drag force of constant$ $magnitude f acts on the stone through$ $out its flight, the speed of stone just$ $before reaching the ground is$

Question Number 20409 Answers: 1 Comments: 1

Calculate the force (F) required to cause the block of mass m_1 = 20 kg just to slide under the block of mass m_2 = 10 kg [coefficient of friction μ = 0.25 for all surfaces]

$C a l c u l a t e t h e f o r c e (F) r e q u i r e d t o$ $c a u s e t h e b l o c k o f m a s s m_{1} = 20 k g$ $j u s t t o s l i d e u n d e r t h e b l o c k o f m a s s$ $m_{2} = 10 k g [c o e f f i c i e n t o f f r i c t i o n μ$ $= 0.25 f o r a l l s u r f a c e s]$

Question Number 20375 Answers: 1 Comments: 1

A small particle of mass m is projected at an angle θ with the x-axis with an initial velocity v_0 in the x-y plane as shown in the Figure. At a time t < ((v_0 sin θ)/g), the angular momentum of the particle is

$A small particle of mass m is projected$ $at an angle θ with the x - axis with an$ $initial velocity v_{0} in the x - y plane as$ $shown in the Figure . At a time$ $t < \frac{v_{0} \sin θ}{g}, the angular momentum of$ $the particle is$

Question Number 20578 Answers: 0 Comments: 2

Tinkutara and Ajfour please how do you do the following using lekh diagram: (i)introduction of dotted lines (ii)writing of letters (iii)shading (iv)putting colours in a diagram (v)draw live figures like birds thanks for the help

$T i n k u t a r a a n d A j f o u r p l e a s e h o w$ $d o y o u d o t h e f o l l o w i n g u s i n g$ $l e k h d i a g r a m :$ $(i) i n t r o d u c t i o n o f d o t t e d l i n e s$ $(i i) w r i t i n g o f l e t t e r s$ $(i i i) s h a d i n g$ $(i v) p u t t i n g c o l o u r s i n a d i a g r a m$ $(v) d r a w l i v e f i g u r e s l i k e b i r d s$ $t h a n k s f o r t h e h e l p$

Question Number 20349 Answers: 0 Comments: 3

A ball rolled on ice with a velocity of 14 ms^(−1) comes to rest after travelling 40 m. Find the coefficient of friction. (Given, g = 9.8 m/s^2 )

$A ball rolled on ice with a velocity of$ $14 {ms}^{- 1} comes to rest after travelling$ $40 m . Find the coefficient of friction .$ $(Given, g = 9.8 m / s^{2})$

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