Method 1. Place a trolley on a smooth runway and tilt the runway very slightly so that the
slope compensate for the friction between the wheels and the runway. If
pushed gently, the trolley should move at a constant velocity.
2. Measure the mass of the trolleys.
3. Attach the ticker timer to the trolley and thread the tape through the ticker
timer.
4. Attach a smooth pulley vertically to the bottom of the runway.