9. an 800 kg police boat slows down uniformly from 50 km/h [e] to 20 km/h (e) as it enters a
harbour. if the boat slows down over a 30 m distance, what is the force of friction on the boat?
(hint: you will need to convert the velocities into m/s.)

The diagram shows a person using a piece of gym equipment to lift weight which best describe the body in terms of simple machine

Lacie kicks a football from ground level at a velocity of 13.9 m/s and at an angle of 25.0° to the ground. how long will the ball be in the air before it lands? how far will the football travel before it lands?

Nitrogen (n2) undergoes an internally reversible process from 6 bar, 247°c during which pν1.2 = constant. the initial volume is 0.1 m3 and the work for the process is 121.14 kj. assuming ideal gas behavior, and neglecting kinetic and potential energy effects, determine heat transfer, in kj, and the entropy change, in kj/s. show the process on a t-s diagram.