A solid sphere is rotating in free space. If the radius of the sphere is increased keeping mass the same which one of the following will not be affected?
Let
be the force acting on a particle having position vector
and
be the torque of this force about the origin. Then
A particle performing uniform circular motion has angular momentum L. If its angular frequency is doubled and its kinetic energy halved, then what would be the new angular momentum?
A circular disc X of radius R is made from an iron plate of thickness t, and another disc Y of radius 4R is made from an iron plate of thickness t/4. Then what is the relation between the moment of inertia Ix and Iy?
A particle of mass m moves along line PC with the velocity v as shown in the below image.
What should be the angular momentum of the particle about P?
What is the moment of inertia of a circular wire of mass M and radius R about its diameter?
A solid sphere, a hollow sphere and a ring are released from top of an inclined plane (frictionless) so that they slide down the plane. Then what is the maximum acceleration down the plane is for (no rolling)?
Initial angular velocity of a circular disc of mass M is 
. Then two small spheres of mass m are attached gently to two diametrically opposite points on the edge of the disc. What is the final angular velocity of the disc?
Initial angular velocity of a circular disc of mass M is . Then two small spheres of mass m are attached gently to two diametrically opposite points on the edge of the disc. What is the final angular velocity of the disc?
What is the velocity of centre of mass if two identical particles move towards each other with velocity 2v and v respectively?
If an electron and a proton having same momenta enter perpendicularly to a magnetic field, then :
Why do we talk in our steep? Why we see unknown faces in the dream.
Why do we talk in our steep? Why we see unknown faces in the dream.
What are paracetamol and steroidal drugs and how a mystery and much work has to be done to join the links do they work?
What is PRIONS
What is VIROIDS
Explain the Lytic cycle of VIRUS.
Explain How Viruses are Intermediate between Living and Non-Living things.
Explain the Types Of VIRUS.
Explain The Virus Components
Explain The Structure of Virus.
Explain The Structure of Virus.
What is VIRUS.
The upper half of an inclined plane with inclination 
perfectly smooth while the lower half is rough. A body starting from rest at the top will again come to rest at the bottom if the coefficient of friction for the lower half is given by
A smooth block is released at rest on a 45° incline and then slides a distance d. The time taken to slide is n times as much to slide on a rough incline than on a smooth incline. What is the coefficient of friction?
An annular ring with inner and outer radii R1 and R2 are rolling without slipping with a uniform angular speed. The ratio of the forces experienced by the two particles situated on the inner and outer parts of the ring, F1 /F2 is
A block rests on a rough inclined plane making an angle of 30° with the horizontal. The coefficient of static friction between the block and the plane is 0.8. If the frictional force on the block is 10 N, then what is the mass of the block (in kg)? [take g = 10 m/s2]
Two masses m1 = 5 kg and m2 = 4.8 kg tied to a string are hanging over a light frictionless pulley. What is the acceleration of the masses when lift free to move? [g = 9.8 m/s2]
A machine gun fires a bullet of mass 40 g with a velocity 1200 m/s-1. The man holding it can exert a maximum force of 144 N on the gun. How many bullets can he fire per second at the most?
A rocket with a lift-off mass 3.5 × 104 kg is blasted upwards with an initial acceleration of 10 m/s2. Then what is the initial thrust of the blast?
A light spring balance hangs from the hook of the other light spring balance and a block of mass M kg hangs from the former one. Then the true statement about the scale reading is
A block of mass M is pulled along a horizontal frictionless surface by a rope of mass m. If a force P is applied at the free end of the rope, then what is the force exerted by the rope on the block?
A marble block of mass 2 kg lying on ice stopped by friction in 10 s when given a velocity of 6 m/s. Then what is the coefficient of friction?
A horizontal force of 10 N is required to just hold a block stationary against a wall. The coefficient of friction between the block and the wall is 0.2. What is the weight of the block?
A spring balance is attached to the ceiling of a lift. A man hangs his bag on the spring and the spring reads 49 N, when the lift is stationary. If the lift moves down with an acceleration of 5 m/s2, what will be the reading of the spring balance?
Three forces start acting simultaneously on a particle moving with velocity 
. These forces are represented in magnitude and direction by the three sides of a triangle ABC (as shown). The particle will now move with velocity
Three identical blocks of masses m 2 kg are drawn by a force F = 10.2 N with an acceleration of 0.6 ms –2 on a frictionless surface, then what is the tension (in N) in the string between the blocks B and C?
A light string passing over a smooth light pulley connects two blocks of masses m1 and m2 (vertically). If the acceleration of the system is g/8, then what is the ratio of the masses?
One end of a massless rope passes over a massless and frictionless pulley P, which is tied to a hook C while the other end is free. Maximum tension that the rope can bear is 960 N. With what value of maximum safe acceleration 
can a man of 60 kg climb on the rope?
When forces 
are acting on a particle of mass m such that 
and 
are mutually perpendicular, then the particle remains stationary. If the force 
is now removed then the acceleration of the particle is
If a lift is moving down with acceleration a. A man in the lift drops a ball inside the lift. What is the acceleration of the ball by the man in the lift and a man standing stationary on the ground?
What is the minimum velocity 
with which a car driver can traverse a flat curve of radius 150 m and coefficient of friction 0.6 to avoid skidding?
A ball of mass 0.2 kg is thrown vertically upwards by applying a force by hand. If the hand moves 0.2 m which applying the force and the ball goes upto 2 m height further, find the magnitude of the force. Consider g = 10 m/s2
The ionization enthalpy of hydrogen atom is 1.312 × 106 J mol–1. The energy required to excite the electron in the atom from n=1 to n=2 is
The de Broglie wavelength of a tennis ball of mass 60 g moving with a velocity of 10 metres per second is approximately
The de Broglie wavelength of a tennis ball of mass 60 g moving with a velocity of 10 metres per second is approximately
In a multielectron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic and electric fields?
(i) n=1,l=0,m=0
(ii) n=2,l=0,m=0
(iii) n=2,l=1,m=1
(iv) n=3,l=2,m=1
(v) n=3,l=2,m=0
According to Bohr’s theory, the angular momentum of an electron in 5th orbit is
Uncertainty in position of a minute particle of mass 25 g in space is 10–5 m. What is the uncertainty in velocity?
In Bohr series of lines of hydrogen spectrum, the third line from the red end corresponds to which one of the following interorbit jumps of the electron for Bohr orbits in an atom of hydrogen?