Chemistry Physical Chemistry Level: Misc Level
The standard enthalpy of combustion of naphthalene is -5157 kJ /mol. Calculate its standard enthalpy of formation.
Chemistry Physical Chemistry Level: Misc Level
The enthalpy changes accompanying the dissociation of succesive bonds in N H 3(g) are 460, 390, and 314 kJ /mol respectively. a) What is the mean enthalpy of an N-H bond?
b) Do you expect the mean bond internal energy to be larger or smaller then the mean bond enthalpy?
Chemistry Mole Concept Level: Misc Level
Calculate the total heat required to melt 100 g of ice at 0 degrees C, heat it to 100 degrees C, and then vaporize it at that temperature. (water std enthalpy of vap = 40.7 kJ /mol)
Physics Modern Physics Level: Misc Level
An electron in an old -fashioned T V camera tube is moving at 10.0 x106 m /s in a magnetic field of strength 110 m T. What is the (a) maximum and (b) minimum magnitude of the force acting on the electron due to the field? (c) At one point the electron has an acceleration of magnitude 5.80 x 10 14 m /s 2.What is the angle between the electron s velocity and the magnetic field?
Physics Modern Physics Level: Misc Level
An electron that has a velocity with x component 2.3 x 10 6 m /s and y component 3.8 x 10 6 m /s moves through a uniform magnetic field with x component 0. 030 T and y component -0.17 T. (a) Find the magnitude of the force on the electron. (b) Repeat your calculation for a proton having the same velocity.
Physics Modern Physics Level: Misc Level
An electron is accelerated from rest by a potential difference of 399 V. It then enters a uniform magnetic field of magnitude 160 m T with its velocity perpendicular to the field. Calculate ( a) the speed of the electron and (b) the radius of its path in the magnetic field.
Physics Modern Physics Level: Misc Level
What uniform magnetic field, applied perpendicular to a beam of electrons moving at 7.31 x 10 6 m /s, is required to make the electrons travel in a circular arc of radius 0.349 m ?
Physics Gravitation Level: Misc Level
The acceleration due to gravity on the moon is about 1.61 m /second squared. What will be the period of a 200 cm long pendulum on the moon?
Physics Waves And Oscillations Level: Misc Level
The acceleration due to gravity on the moon is about 1.61 m /second squared. What will be the period of a 200 cm long pendulum on the moon?
Physics Waves And Oscillations Level: Misc Level
( 2 parts ) A 14 kg motor is mounted on rubber feet. The motor can be pulled aside a distance of 0.50 cm by a force of 200 N. a) Find the spring constant for the sideways motion of the motor.
b) what is the natural frequency for sideways vibration of the motor?
Physics Work,Power & Energy Level: Misc Level
A washer ( 5.0 g ) sits at the end of a horizontal spring ( k= 100 N/ m ) which is slipped over a large bolt. The washer is pressed back against the spring so as to compress it 2.0 cm. How fast will the washer shoot off the bolt if the washer is released?
Physics Waves And Oscillations Level: Misc Level
A 0.50 kg mass vibrates with amplitude 4.0 cm at the end of a spring, whose constant is 25 N /m. Find the acceleration of the mass when its displacement from equilibrium is 3.0 cm.
Physics Ray Optics Level: Misc Level
Two lenses are both converging, and each has a 20 cm focal length. They are placed 40 cm apart. A 5 cm high object is placed 80 cm in front of the lens. find the final image position and its Size. Is it Real ? Is it Upright?
Physics Ray Optics Level: Misc Level
It is desired to use a 60 cm focal length diverging lens to from a virtual image of an object. The image is to be one - third as large as the object. a) Where should the object be placed relative to the lens? b) What will be the image distance?
Physics Ray Optics Level: Misc Level
An object is imaged by a covering lens of 40 cm focal length. Find the image position by means of a" Ray diagram" for the following object distances. ( note : you can draw object to any height you want besides 5 cm ) a) 80 cm b) 50 cm c) 20 cm. in each case is the image Real ? Upright?
