1 A camshaft inside an engine is rotating with angular speed \(42 \mathrm { rads } ^ { - 1 }\). When the throttle is opened the camshaft speeds up with constant angular acceleration, and 8 seconds after the throttle was opened the angular speed is \(76 \mathrm { rad } \mathrm { s } ^ { - 1 }\).

1. Find the angular acceleration of the camshaft.
2. Find the time taken for the camshaft to turn through 810 radians from the moment that the throttle was opened.