Quantum Mechanics Answers

If the work function for a metal is 1.8 eV, what would be the stopping potential for light having a wavelength of 400 nm? (b) What would be the maximum velocity of the emitted photoelectrons at the metal’s surface? 

prove that velocity of light is 3×10^8 ?

Calculate the moment of inertia of a thin uniform rod that is 1.45 m long and has a mass of 5 kg

around an axis at right angles to the rod and through the center.

How physics relate to our daily Lives?

Give a situation in real life where physics apply, Or it can be mathematical problem where it can related to our daily lives.

A 400.0-N sign hangs from the end of a uniform strut. The strut is 4.0 m long and

weighs 600.0 N. The strut is supported by a hinge at the wall and by a cable whose

other end is tied to the wall at a point 3.0 m above the left end of the strut. Find the

tension in the supporting cable and the force of the hinge on the strut.

A 50-kg person stands 1.5 m away from one end of a uniform 6.0-m-long scaffold of mass 70.0 kg. Find the tensions in the two vertical ropes supporting the scaffold.

Three masses are attached to a uniform meter stick, as shown in Figure 12.9.. The mass of the meter stick is 150.0 g and the masses to the left of the fulcrum are m1=50.0gm1=50.0g and m2=75.0g.m2=75.0g. Find the mass m3m3 that balances the system when it is attached at the right end of the stick, and the normal reaction force at the fulcrum when the system is balanced.

A box rests on a frozen pond, which serves as a frictionless

horizontal surface. If a fisherman applies a horizontal force with magnitude 48.0 N to the box and produces an acceleration of magnitude 3.00 m/s², what is the mass of the box?

Statistical physics I (chapter 3)

Consider a system which consists of two subsystems A and A’ which can interact to a small extent and thus exchange energy with each other. System A consists three spins, each having a magnetic moment . System A’ consists of two spins , each having a magnetic moment 2 . Suppose that, when the systems A and A’ are initially separated from each other, measurements show the total magnetic moment of A to be and the total magnetic moment of A’ to be . The systems are now placed in thermal contact with each other and are allowed to exchange energy until the final equilibrium situation has been reached. Under these conditions calculate:

The probability p(M) that the total magnetic moment of A assumes any one of its possible values M.

The mean value of the total magnetic moment of A.

Suppose that the systems are now again separated so that they are no longer free to exchange energy with each other. What are the values of p(M) and of the system A after this separation?

A calesa pulled by a horse carries a 75.0-kg load containing copies of modules to be distributed in remote barangays. The calesa has a mass of 2.50 x 103 kg. If the calesa moves accelerates at a rate of 4.00 m/s2 , how much pull was exerted by the horse?