Q1. A racing car of mass 1965 kg accelerates from 160km/hr to 240km/hr in 3.5 seconds. Calculate, i) Average acceleration ii) Force required to produce acceleration

Q2. a) What is the work done in lifting a mass of 2000kg vertically to a height

of 40 meters?

b) What is the kinetic energy of a 2 kg object that travels a distance of

50 metres in 5 seconds?

c) You must exert a force of 4.5N on a book to slide it across a table. If 2.7J

of work is done in the process, how far have you moved the book?

d) A 1kg weight held 5 m above the ground level should possess a potential

energy of?

e) A 3.91N baseball has 775J of kinetic energy. How fast is it moving?

Q 3.a) State Law of Conservation of energy.

b) A 190,000W engine can accelerate from rest to a top speed in 9seconds.

How much work did the engine do?

`c) An elevator must lift 1000 kg a distance of 100m at a velocity of 4m/s.

What is the average power the elevator exerts during this trip?

Q4. a) Calculate the velocity of a body of mass 1kg having a momentum of 10 Ns.

b)Engines of a jet aircraft travelling at a speed of 250m/s exert a thrust force

of 24.5kN. Determine the power developed.

c) A machine with an efficiency of 80% raises a load of 100 N vertically to a

height of 5m. What is the work input to the machine?