State whether the following objects possess kinetic energy, potential energy, or both : (a) A man climbing a hill (b) A flying aeroplane (c) A bird running on the ground (d) A ceiling fan in the off position (e) A stretched spring lying on the grund.
What kind of energy is possessed by the following ? (a) A stone kept on roof-top. (b) A running car. (c) Water stored in the reservoir of a dam. (d) A compressed spring. (e) A stretched rubber band.
In figure, k = 100 N//m, M = 1kg and F = 10 N (a) Find the compression of the spring in the equilibrium position (b) A sharp blow by some external agent imparts a speed of 2 m//s to the block towards left. Find the sum of the potential energy of the spring and the kinetic energy of the block at this instant. (c) Find the time period of the resulting simple harmonic motion. (d) Find the amplitude. (e) Write the potential energy of the spring when the block is at the left estreme. (f) Write the potential energy of the spring when the block is at the right extreme. The answers of (b), (e) and (f) are different. Explain why this does not violate the principle of conservation of energy ?
Consider a one-dimensional motion of a particle with total energy E. There are four regions A, B, C and D is which the relation between potential energy U, kinetic energy (K) and total energy E is as given below RegionA: UgtE Region B: UltE Region C: KltE Region D: UgtE State with reason in each case whether a particle can be found in the given region or not.
As an electron makes a transition from an excited state to the ground state of a hydrogen like atom/ion (a) kinetic energy, potential energy and total energy decrease (b) kinetic energy decreases, potential energy increases but total energy remains same (c ) kinetic energy and total energy decrease but potential energy increases (d) its kinetic energy increases but potential energy and total energy decrease
A point mass m starts from rest and slides down the surface of a frictionless hemisphere of radius r as shown figure. Measure angle from the vertical and potential energy from the top. Find a. Find the changes in potential energy of the mass with angle b. Find the kinetic energy as a function of angle c. Find the radial and tangential acceleration as a function of angle d. Find the angle at which the mass files off the hemisphere e. If there is friction between the mass and hemisphere, does the mass fly off at a greater or lesser angle than in part (d) ?
Light of wavelength 2000 Å falls on an aluminium surface . In aluminium 4.2 e V of energy is required to remove an electron from its surface. What is the kinetic energy , in electron volt of (a) the fastest and (b) the slowest emitted photo-electron . ( c) What is the stopping potential ? (d) What is the cut - off wavelength for aluminum? (Plank's constant h = 6.6 xx 10^(-34) J-s and speed of light c = 3 xx 10^(8) m s^(-1).
In the photoelectric effect, suppose that the intensity of the light is increased, while the frequency is kept constant. The frequency is greater than the minimum frequency f_(0) . State whether each of the following will increases, decrease, or remain constant, and explain your choice. (a) the current in the phototube, (b) the number of electrons per second from the metal surface, c) the maximum kinetic energy that an electron could have, d) the maximum momentum that an electron could have, and e) the maximum de-Broglie wavelength that an electron could have.
A mass of 0.5 kg is hung from a spring. Agradually increasing 0.5 N force is reuired topull the mass downward a distance of 0.25 m from its equilibrium position,if the mass s then released from this position, find (a) The total energy of the system . (b) The frequency of the oscillation (c ) The speed and acceleration of the mass as it passes the equilibrium position. (d) The speed and acceleration of the mas when the diplacement from equilibrium is 0.25 m (e) For the initial condition stated, write down the diplacement equation of motion for this mass.
LAKHMIR SINGH & MANJIT KAUR-MODEL TEST PAPER 1-SECTION B
