Physics-
General
Easy
Question
Two blocks of equal mass m are connected by an unstretched spring, and the system is kept at rest on a frictionless horizontal surface. A constant force F is applied on the first block pulling it away from the other as shown in figure Then the displacement of the centre of mass at time t is:-
The correct answer is:
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An initially stationary box on a frictionless floor explodes into two pieces, piece A with mass 
and piece B with mass 
. Two pieces then move across the floor along x–axis. Graph of position versus time for the two pieces are given If all the graphs are possible then, in which of the following cases external force must be acting on the box :-
An initially stationary box on a frictionless floor explodes into two pieces, piece A with mass and piece B with mass . Two pieces then move across the floor along x–axis. Graph of position versus time for the two pieces are given If all the graphs are possible then, in which of the following cases external force must be acting on the box :-
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When the mass of a system is variable, a thrust force has to be applied on it in addition to all other forces acting on it. This thrust force is given by 
Here 
is the relative velocity with which the mass dm either enters or leaves the system. A car has total mass 50 kg. Gases are ejected from this backwards with relative velocity 20 m/s. The rate of ejection of gas is 2 kg/s. Total mass of gas is 20 kg. Coefficient of friction between the car and road is 
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When the mass of a system is variable, a thrust force has to be applied on it in addition to all other forces acting on it. This thrust force is given by Here is the relative velocity with which the mass dm either enters or leaves the system. A car has total mass 50 kg. Gases are ejected from this backwards with relative velocity 20 m/s. The rate of ejection of gas is 2 kg/s. Total mass of gas is 20 kg. Coefficient of friction between the car and road is = 0.1 Car will stop after (from starting) t = .... seconds :
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When the mass of a system is variable, a thrust force has to be applied on it in addition to all other forces acting on it. This thrust force is given by Here is the relative velocity with which the mass dm either enters or leaves the system. A car has total mass 50 kg. Gases are ejected from this backwards with relative velocity 20 m/s. The rate of ejection of gas is 2 kg/total mass of gas is 20 kg. Coefficient of friction between the car and road is = 0.1 Maximum speed of car will be v = ..... m/s 
When the mass of a system is variable, a thrust force has to be applied on it in addition to all other forces acting on it. This thrust force is given by Here is the relative velocity with which the mass dm either enters or leaves the system. A car has total mass 50 kg. Gases are ejected from this backwards with relative velocity 20 m/s. The rate of ejection of gas is 2 kg/total mass of gas is 20 kg. Coefficient of friction between the car and road is = 0.1 Maximum speed of car will be v = ..... m/s
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Two open organ pipes gives 4 beats/sec when sounded together in their fundamental nodes. If the length of the pipe are 
and 
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An earthquake generates both transverse (s) and longitudinal (p) sound waves in the earth. The speed of S waves is about 4.5 m/s and that of 
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A source of sound is travelling towards a stationary observer. The frequency of sound heard by the observer is of three times the original frequency. The velocity of sound is vm/ sec. The speed of source will be
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When the mass of a system is variable, a thrust force has to be applied on it in addition to all other forces acting on it. This thrust force is given by Here is the relative velocity with which the mass d m either enters or leaves the system. A car has total mass 50 kg. Gases are ejected from this backwards with relative velocity 20 m/s. The rate of ejection of gas is 2 kg/total mass of gas is 20 kg. Coefficient of friction between the car and road is = 0.1 Car will start moving after time t = . .. second:
When the mass of a system is variable, a thrust force has to be applied on it in addition to all other forces acting on it. This thrust force is given by Here is the relative velocity with which the mass d m either enters or leaves the system. A car has total mass 50 kg. Gases are ejected from this backwards with relative velocity 20 m/s. The rate of ejection of gas is 2 kg/total mass of gas is 20 kg. Coefficient of friction between the car and road is = 0.1 Car will start moving after time t = . .. second:
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In an oblique collision component parallel to common tangent remains unchanged while along common normal direction, relative velocity of separation becomes e times the relative velocity of approach. A ball collides at B with velocity 10 m/s at 30° with vertical. There is a flag at A and a wall at C. Collision of ball with ground is perfectly inelastic (e = 0) and that with wall is elastic (e = 1). Given AB = BC = 10m. The ball will collide with the flag after time t = ....s
In an oblique collision component parallel to common tangent remains unchanged while along common normal direction, relative velocity of separation becomes e times the relative velocity of approach. A ball collides at B with velocity 10 m/s at 30° with vertical. There is a flag at A and a wall at C. Collision of ball with ground is perfectly inelastic (e = 0) and that with wall is elastic (e = 1). Given AB = BC = 10m. The ball will collide with the flag after time t = ....s
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If net force on a system in a particular direction is zero (say in horizontal direction) we can apply: 
Here R stands for the masses which are moving towards right and L for the masses towards left, x is displacement, v is velocity and a the acceleration (all with respect to ground). A small block of mass m = 1 kg is placed over a wedge of mass M = 4 kg as shown in figure. Mass m is released from rest. All surfaces are smooth. Origin O is as shown. At the same instant reaction on the wedge from the ground is N
If net force on a system in a particular direction is zero (say in horizontal direction) we can apply: Here R stands for the masses which are moving towards right and L for the masses towards left, x is displacement, v is velocity and a the acceleration (all with respect to ground). A small block of mass m = 1 kg is placed over a wedge of mass M = 4 kg as shown in figure. Mass m is released from rest. All surfaces are smooth. Origin O is as shown. At the same instant reaction on the wedge from the ground is N
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physics-
If net force on a system in a particular direction is zero (say in horizontal direction) we can apply: Here R stands for the masses which are moving towards right and L for the masses towards left, x is displacement, v is velocity and a the acceleration (all with respect to ground). A small block of mass m = 1 kg is placed over a wedge of mass M = 4 kg as shown in figure. Mass m is released from rest. All surfaces are smooth. Origin O is as shown. Normal reaction between the two blocks at an instant when absolute acceleration of m is 
m/s2 at 60° with horizontal is N. Normal reaction at this instant is making 
with horizontal:
If net force on a system in a particular direction is zero (say in horizontal direction) we can apply: Here R stands for the masses which are moving towards right and L for the masses towards left, x is displacement, v is velocity and a the acceleration (all with respect to ground). A small block of mass m = 1 kg is placed over a wedge of mass M = 4 kg as shown in figure. Mass m is released from rest. All surfaces are smooth. Origin O is as shown. Normal reaction between the two blocks at an instant when absolute acceleration of m is m/s2 at 60° with horizontal is N. Normal reaction at this instant is making with horizontal:
physics-General
physics-
If net force on a system in a particular direction is zero (say in horizontal direction) we can apply: Here R stands for the masses which are moving towards right and L for the masses towards left, x is displacement, v is velocity and a the acceleration (all with respect to ground). A small block of mass m = 1 kg is placed over a wedge of mass M = 4 kg as shown in figure. Mass m is released from rest. All surfaces are smooth. Origin O is as shown. The block will strike the x–axis at x = ....m :–
If net force on a system in a particular direction is zero (say in horizontal direction) we can apply: Here R stands for the masses which are moving towards right and L for the masses towards left, x is displacement, v is velocity and a the acceleration (all with respect to ground). A small block of mass m = 1 kg is placed over a wedge of mass M = 4 kg as shown in figure. Mass m is released from rest. All surfaces are smooth. Origin O is as shown. The block will strike the x–axis at x = ....m :–
physics-General
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If net force on a system in a particular direction is zero (say in horizontal direction) we can apply: Here R stands for the masses which are moving towards right and L for the masses towards left, x is displacement, v is velocity and a the acceleration (all with respect to ground). A small block of mass m = 1 kg is placed over a wedge of mass M = 4 kg as shown in figure. Mass m is released from rest. All surfaces are smooth. Origin O is as shown. Final velocity of the wedge is m/s :–
If net force on a system in a particular direction is zero (say in horizontal direction) we can apply: Here R stands for the masses which are moving towards right and L for the masses towards left, x is displacement, v is velocity and a the acceleration (all with respect to ground). A small block of mass m = 1 kg is placed over a wedge of mass M = 4 kg as shown in figure. Mass m is released from rest. All surfaces are smooth. Origin O is as shown. Final velocity of the wedge is m/s :–
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When two bodies collide normally, they exert equal and opposite impulses on each other. Impulse = change in linear momentum. Coefficient of restitution between two bodies is given by :– 
for elastic collision Two bodies collide as shown in figure. During collision they exert impulse of magnitude J on each other. For what values of J (in N–s) the 2 kg block will change its direction of velocity :
When two bodies collide normally, they exert equal and opposite impulses on each other. Impulse = change in linear momentum. Coefficient of restitution between two bodies is given by :– for elastic collision Two bodies collide as shown in figure. During collision they exert impulse of magnitude J on each other. For what values of J (in N–s) the 2 kg block will change its direction of velocity :
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