1. How many kg of coal are used to supply 1500 Watts to heat a barn for 7 hours? The energy content of coal is 19 x 106 J/kg.
2. a) Two masses are positioned on a curved, frictionless track as shown. If the 7.2 kg mass is released from a height, h, of 2.0 m and slides down the track, with what speed does it strike the 49 kg mass?
b) After it strikes the 49 kg mass, the larger mass recoils with a speed of 1.604 m/s. Assuming the collision is elastic, write out the equation(s) you would require to solve for the recoil speed. Note: you don’t need to solve for it, I’ve already done that for you. Just show me the starting point.
c) If the speed with which the 49 kg mass recoils is 1.604 m/s, then how high up (distance) the track does the 7.2 kg mass bounce?
3. James bond (mass 78 kg) is running to catch a bag (mass 23 kg) containing an antiserum to a deadly disease. Initially Mr. Bond is running 4.4 m/s north and the bag is travelling 2.9 m/s east. What is the final velocity (magnitude and direction) of James and the bag immediately after the catch (collision).
4. [8] In an oscilloscope, an electron is accelerated from rest through a voltage of 1.14 x 103 V it then passes through deflecting plates 2.00 cm apart, across which there is a voltage of 412 V. Its velocity when it enters the plate is perpendicular to the electric field of the plates. When the electron leaves the plates, what distance will it have moved toward the positive plate?
5. In the configuration shown below, what is the current flowing through the battery?
What is the current flowing through the 100 Ω resistor?
