Answer:
1. Torque → F. Study of forces
2. C.O.G → D. Point of action of weight.
3. Plumb line → A. Line of C.O.G
Well I know that ernest rutherford did the gold foil experiment where he fired alpha particles at gold foil. This experiment founded the nucleus but I don't know if the current model of the atom is based on this.
Cathode ray tube experiments sounds like its to do with electrolysis so i dont think it can be that.
30mi/6hrs is a speed of 5 mph, which converts to a pace of 12 min/mi.
Answer:0.27
Explanation:
Given
One worker Pushes with force 
other Pulls it with a rope of rope 
mass of crate 
both forces are horizontal and crate slides with a constant speed
Both forces are in the same direction so Friction will oppose the forces and will be equal in magnitude of sum of two forces because crate is moving with constant speed i.e. net force is zero on it

where
is the friction force



where
is the coefficient of static friction


