A motor is used to raise a lift of mass 200 kg and 4 passengers each of whom has an average mass of 65 kg. They wish to go to the third floor, which is 12 m above them. If the motor is 45% efficient, what
input of electrical energy is required?
Give your answer in kJ.
(Show work)

In a vernier instrument the main scale is in 1/2 mm divisions .vernier is made by redividing 19 such divisions into 20 equal parts. calculate the least count of the instrument.

Aboxcar traveling at 12 m/s approaches a string of 5 identical boxcars sitting stationary on the track. the moving boxcar collides and links with the stationary cars and they all move off together along the track. what is the final speed of the cars immediately after the collision? (you may take the mass of each boxcar to be 18,537 kg.)

Awave is produced in a rope. the wave has a speed of 33 m/s and a frequency of 22 hz. what wavelength is produced?